AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MAY 17, 1999
REGISTRATION NO. 333-


SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549


FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933


PS BUSINESS PARKS, INC.
(EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)


           CALIFORNIA                                      95-4300881
  (STATE OR OTHER JURISDICTION                          (I.R.S. EMPLOYER
OF INCORPORATION OR ORGANIZATION)                     IDENTIFICATION NO.)

701 WESTERN AVENUE
GLENDALE, CALIFORNIA 91201-2397
(818) 244-8080
(ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA CODE, OF
REGISTRANT'S PRINCIPAL EXECUTIVE OFFICES)


HARVEY LENKIN
PS BUSINESS PARKS, INC.
701 WESTERN AVENUE
GLENDALE, CALIFORNIA 91201-2397
(818) 244-8080
(NAME, ADDRESS, INCLUDING ZIP CODE, AND TELEPHONE NUMBER, INCLUDING AREA CODE,
OF AGENT FOR SERVICE)

COPIES TO:
DAVID GOLDBERG, ESQ.
PS BUSINESS PARKS, INC.
701 WESTERN AVENUE
GLENDALE, CALIFORNIA 91201-2397


APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time

to time after the effective date of this Registration Statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. [_]

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. [X]

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. [_]

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. [_]

If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. [X]


CALCULATION OF REGISTRATION FEE

----------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------
                                                     Proposed
                                                     Maximum        Proposed
                                       Amount     Offering Price    Maximum       Amount of
     Title of Each Class of            to be       per Share or    Aggregate     Registration
   Securities to be Registered       Registered        Unit      Offering Price      Fee
----------------------------------------------------------------------------------------------
Common Stock, $.01 par value
 per share......................       (1)(3)          (2)         (1)(2)(3)           N/A
Preferred Stock, $.01 par value
 per share......................       (1)(4)          (2)         (1)(2)(4)           N/A
Depositary Shares Representing
 Interests in Preferred Stock...       (1)(4)          (2)         (1)(2)(4)           N/A
Equity Stock, $.01 par value per
 share..........................       (1)(5)          (2)         (1)(2)(5)           N/A
Depositary Shares Representing
 Interests in Equity Stock......       (1)(5)          (2)         (1)(2)(5)           N/A
Warrants........................       (1)(6)          (2)         (1)(2)(6)           N/A
 Total..........................  $279,509,083(7)      (2)        $279,509,083(7)   $77,703.53(8)

-------------------------------------------------------------------------------------------------
-------------------------------------------------------------------------------------------------

(1) In no event will the aggregate maximum offering price of all securities issued pursuant to this Registration Statement exceed $279,509,083. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. 6,139,356 shares of Common Stock at a proposed maximum aggregate offering price of $160,774,386 (pursuant to Rule 457(c), based on the average of the high and low prices of the Common Stock on the American Stock Exchange on May 12, 1999) being registered are being allocated to registered resales in secondary offerings (includes any securities issuable upon stock splits and similar transactions pursuant to Rule 416).
(2) The proposed maximum offering price per unit will be determined, from time to time, by the Registrant in connection with the issuance by the Registrant of the securities registered hereunder. No separate consideration will be received for any Depositary Shares representing shares of Preferred Stock of the Registrant.
(3) Subject to Footnote 1, there is being registered hereunder an indeterminate number of shares of Common Stock as may be sold, from time to time, by the Registrant. There is also being registered hereunder an indeterminate number of shares of Common Stock as shall be issuable upon conversion of the Preferred Stock or the Equity Stock or exercise of Warrants registered hereby.
(4) Subject to Footnote 1, there is being registered hereunder an indeterminate number of shares of Preferred Stock, and Depositary Shares representing a fractional interest in a share of Preferred Stock, as may be sold, from time to time, by the Registrant. In the event Registrant elects to offer to the public fractional interests in shares of the Preferred Stock registered hereunder, Depositary Receipts will be distributed to those persons acquiring such fractional interests and the shares of Preferred Stock will be issued to a Depositary under a Deposit Agreement. There is also being registered hereunder an indeterminate number of shares of Preferred Stock as shall be issuable upon exercise of Warrants registered hereby.
(5) Subject to Footnote 1, there is being registered hereunder an indeterminate number of shares of Equity Stock, and Depositary Shares representing a fractional interest in a share of Equity Stock, as may be sold, from time to time, by the Registrant. In the event Registrant elects to offer to the public fractional interests in shares of the Equity Stock registered hereunder, Depositary Receipts will be distributed to those persons acquiring such fractional interests and the shares of Equity Stock will be issued to a Depository under a Deposit Agreement. There is also being registered hereunder an indeterminate number of shares of Equity Stock as shall be issuable upon exercise of Warrants registered hereby.
(6) Subject to Footnote 1, there is being registered hereunder an indeterminate number of Warrants representing rights to purchase Common Stock, Preferred Stock or Equity Stock, as the case may be, registered pursuant to this Registration Statement.
(7) An additional $320,490,917 of securities were registered by Registrant under Registration Statement No. 333-50463 (including $110,959,257 allocated to registered resales in secondary offerings) and remain unissued or unsold.
(8) Calculated pursuant to Rule 457(o) of the rules and regulations under the Securities Act of 1933, as amended. $44,695.28 of the registration fee has been allocated to the registration of the securities described in Footnote 1 for registered resales in secondary offerings. An additional $94,545 registration fee was paid by Registrant in connection with Registration Statement No. 333-50463 (including $32,733 allocated to registered resales in secondary offerings) with respect to securities registered thereunder that remain unissued or unsold.


PURSUANT TO RULE 429 OF THE RULES AND REGULATIONS UNDER THE SECURITIES ACT OF 1933, THE PROSPECTUS WHICH IS A PART OF THIS REGISTRATION STATEMENT WILL ALSO BE USED IN CONNECTION WITH SECURITIES REGISTERED BY REGISTRANT'S REGISTRATION STATEMENT NO. 333-50463. IN THE EVENT ANY OF SUCH PREVIOUSLY REGISTERED SECURITIES ARE OFFERED PRIOR TO THE EFFECTIVE DATE OF THIS REGISTRATION STATEMENT THEY WILL NOT BE INCLUDED IN SUCH PROSPECTUS.

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH
SECTION 8(a) OF THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID
SECTION 8(a), MAY DETERMINE.




PS Business Parks, Inc.

By this prospectus, we may offer-

Common Stock
Preferred Stock
Equity Stock
Depositary Shares
Warrants

We will provide the specific terms of these securities in supplements to this prospectus. You should read this prospectus and the supplements carefully before you invest.

This prospectus may also be used in registered resales of common stock as described under "Plan of Distribution."

Please read "Risk Factors" beginning on page 1 for a discussion of material risks you should consider before you invest.

Neither the Securities and Exchange Commission nor any state securities regulator has approved or disapproved the securities to be issued under this prospectus or determined if this prospectus is accurate or adequate. Any representation to the contrary is a criminal offense.

May , 1999


You should rely only on the information contained in or incorporated by reference in this prospectus supplement or the accompanying prospectus. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information contained in or incorporated by reference in this prospectus supplement or the accompanying prospectus is accurate as of any date other than the date on the front of this prospectus supplement.


TABLE OF CONTENTS

                                                                           Page
                                                                           ----
Risk Factors
  We are controlled by Public Storage.....................................   1
  Provisions in our organizational documents may prevent changes in
   control................................................................   1
  Our operating partnership poses additional risks to us..................   1
  We cannot sell certain properties without Public Storage's approval.....   2
  Certain institutional investors have special rights.....................   2
  We would incur adverse tax consequences if we fail to qualify as a
   REIT...................................................................   2
  Since we buy and operate real estate, we are subject to the general real
   estate investment and operating risks..................................   2
  Our ability to control our properties may be adversely affected by
   ownership through partnerships and joint ventures......................   4
  We can change our business policies and increase our level of debt
   without shareholder approval...........................................   4
  We can issue additional securities without shareholder approval.........   4
  Increases in interest rates may adversely affect the market price of our
   common stock...........................................................   4
  Shares that become available for future sale may adversely affect the
   market price of our common stock.......................................   5
  We depend on key personnel..............................................   5
About This Prospectus.....................................................   5
Where You Can Find More Information.......................................   6
Forward Looking Statements................................................   7
The Company...............................................................   7
Use of Proceeds...........................................................   8
Ratio of Earnings to Fixed Charges........................................   8
Description of Common Stock...............................................   8
  Common Stock............................................................   8
  Ownership Limitations...................................................   9
Description of Preferred Stock............................................  10
  Outstanding Preferred Stock.............................................  10
  Ownership Limitations...................................................  11
  Future Series of Preferred Stock........................................  11
Description of Equity Stock...............................................  14
  Ownership Limitations...................................................  15
  Terms of Equity Stock...................................................  15
Description of the Depositary Shares......................................  17
  Dividends...............................................................  17
  Liquidation Rights......................................................  17
  Redemption..............................................................  18
  Conversion..............................................................  18
  Voting..................................................................  18
  Withdrawal of Preferred Stock...........................................  18
  Amendment and Termination of Deposit Agreement..........................  18


TABLE OF CONTENTS--(Continued)

                                                                           Page
                                                                           ----
  Charges of Depositary...................................................  19
  Miscellaneous...........................................................  19
  Resignation and Removal of Depositary...................................  19
  Federal Income Tax Considerations.......................................  19
Description of Warrants...................................................  20
Certain Federal Income Tax Considerations.................................  20
  Taxation of the Company.................................................  21
  Taxation of U.S. Shareholders Holding Common Stock......................  26
  Taxation of Non-U.S. Shareholders.......................................  28
  Administration's Proposed Changes to REIT Qualification Requirements....  30
  Tax Aspects of the Company's Ownership of Interests in the Operating
   Partnership............................................................  31
  Taxation of Holders of Preferred Stock, Equity Stock, Depositary Shares
   and Warrants...........................................................  33
  State and Local Taxes...................................................  33
Plan of Distribution......................................................  33
Legal Opinions............................................................  36
Experts...................................................................  36


RISK FACTORS

Before investing in our securities, you should consider the following risks and detriments:

We are controlled by Public Storage.

Public Storage owns a substantial number of our shares. At April 30, 1999, Public Storage owned 22% of the outstanding shares of our common stock (41% upon conversion of its interest in our operating partnership). Consequently, Public Storage has the ability to effectively control all matters submitted to a vote of our shareholders, including electing directors, changing our articles of incorporation, dissolving and approving other extraordinary transactions. In addition, Public Storage's ownership may make it more difficult for another party to take over our company without Public Storage's approval.

Public Storage has a voting agreement with another large shareholder. Public Storage and an institutional shareholder owning 26% of our common stock as of April 30, 1999 have both agreed to vote their shares to support specified nominees to our board of directors until the voting agreement expires, which is not before December 2001. This voting agreement further strengthens Public Storage's control of our company.

Provisions in our organizational documents may prevent changes in control.

Our articles generally prohibit owning more than 7% of our shares. Our articles of incorporation restrict the number of shares that may be owned by any other person, and the partnership agreement of our operating partnership contains an anti-takeover provision. No shareholder (other than Public Storage and certain other specified shareholders) may own more than 7% of the outstanding shares of our common stock, unless our board of directors waives this limitation. We imposed this limitation to avoid, to the extent possible, a concentration of ownership that might jeopardize our ability to qualify as a real estate investment trust, or REIT. This limitation, however, also makes a change of control much more difficult (if not impossible) even if it may be favorable to our public shareholders. These provisions will prevent future takeover attempts not approved by Public Storage even if a majority of our public shareholders consider it to be in their best interests because they would receive a premium for their shares over the shares' then market value or for other reasons.

Our board can set the terms of certain securities without shareholder approval. Our board of directors is authorized, without shareholder approval, to issue up to 50,000,000 shares of preferred stock and up to 100,000,000 shares of equity stock, in each case in one or more series. Our board has the right to set the terms of each of these series of stock. Consequently, the board could set the terms of a series of stock that could make it difficult (if not impossible) for another party to take over our company even if it might be favorable to our public shareholders. Our articles of incorporation also contain other provisions that could have the same effect. We can also cause our operating partnership to issue additional interests for cash or in exchange for property.

The partnership agreement of our operating partnership restricts mergers. The partnership agreement of our operating partnership provides that generally we may not merge or engage in a similar transaction unless limited partners of our operating partnership are entitled to receive the same proportionate payments as our shareholders. Also we have agreed not to merge unless the merger would have been approved had the limited partners been able to vote together with our shareholders. These provisions may also make it more difficult for us to merge.

Our operating partnership poses additional risks to us.

Limited partners of our operating partnership, including Public Storage, have the right to vote on certain changes to the partnership agreement. They may vote in a way that is against the interests of our shareholders. Also, as general partner of our operating partnership, we are required to protect the interests of the limited partners of our operating partnership. The interests of the limited partners and of our shareholders may differ.


We cannot sell certain properties without Public Storage's approval.

Before 2007, we may not sell 13 specified properties without Public Storage's approval. Since Public Storage would be taxed on a sale of these properties, the interests of Public Storage and our shareholders may differ as to the best time to sell.

Certain institutional investors have special rights.

Certain institutional investors have rights, such as the right to approve nominees to our board of directors, the right to purchase our securities in certain circumstances and the right to require registration of their shares, not available to our public shareholders.

We would incur adverse tax consequences if we fail to qualify as a REIT.

Our cash flow is reduced if we fail to qualify as a REIT. While we believe that we have qualified since 1990 to be taxed as a REIT, and will continue to be qualified, we cannot be certain. To continue to qualify as a REIT, we need to satisfy certain requirements under the federal income tax laws relating to our income, assets, distributions to shareholders and shareholder base. In this regard, the share ownership limits in our articles of incorporation do not necessarily ensure that our shareholder base is sufficiently diverse for us to qualify as a REIT. For any year we fail to qualify as a REIT, we would be taxed at regular corporate tax rates on our taxable income unless certain relief provisions apply. Taxes would reduce our cash available for distributions to shareholders or for reinvestment, which could adversely affect us and our shareholders. Also we would not be allowed to elect REIT status for five years after we fail to qualify unless certain relief provisions apply.

Our cash flow is reduced if our predecessor failed to qualify as a REIT. For us to qualify to be taxed as a REIT, our predecessor, American Office Park Properties, also needed to qualify to be taxed as a REIT. We believe American Office Park Properties qualified as a REIT beginning in 1997 until its March 1998 merger with us. If it is determined that it did not qualify as a REIT, we could also lose our REIT qualification. Before 1997, our predecessor was a taxable corporation and, to qualify as a REIT, was required to distribute all of its profits before the end of 1996. While we believe American Office Park Properties qualified as a REIT since 1997, we did not obtain an opinion of an outside expert at the time of its merger with us.

We may need to borrow funds to meet our REIT distribution requirements. To qualify as a REIT, we must generally distribute to our shareholders 95% of our taxable income. Our income consists primarily of our share of our operating partnership's income. We intend to make sufficient distributions to qualify as a REIT and otherwise avoid corporate tax. However, differences in timing between income and expenses and the need to make nondeductible expenditures such as capital improvements and principal payments on debt could force us to borrow funds to make necessary shareholder distributions.

Since we buy and operate real estate, we are subject to the general real estate investment and operating risks.

Summary of real estate risks. We own and operate commercial properties and are subject to the risks of owning real estate generally and commercial properties in particular. These risks include:

. the national, state and local economic climate and real estate conditions, such as oversupply of or reduced demand for space and changes in market rental rates;

. how prospective tenants perceive the attractiveness, convenience and safety of our properties;

. our ability to provide adequate management, maintenance and insurance;

. our ability to collect rent from tenants on a timely basis;

. the expense of periodically renovating, repairing and reletting spaces;

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. increasing operating costs, including real estate taxes and utilities, if these increased costs cannot be passed through to tenants; and

. changes in tax, real estate and zoning laws.

Certain significant costs, such as mortgage payments, real estate taxes, insurance and maintenance costs, generally are not reduced even when a property's rental income is reduced. In addition, environmental and tax laws, interest rate levels, the availability of financing and other factors may affect real estate values and property income. Furthermore, the supply of commercial space fluctuates with market conditions.

If our properties do not generate sufficient income to meet operating expenses, including any debt service, tenant improvements, leasing commissions and other capital expenditures, we may have to borrow additional amounts to cover fixed costs, and we may have to reduce our distributions to shareholders.

We only recently acquired many of our properties. We have recently acquired many of our properties and intend to continue to acquire additional properties. As of March 31, 1999, approximately 36% of our properties' square footage was not managed by us before January 1, 1998. We may not be aware of problems with newly acquired properties that could affect their value, and their operating performance may be less than we anticipate. Also, we may have difficulty integrating new acquisitions into our existing portfolio.

We may encounter significant delays in reletting vacant space, resulting in losses of income. When leases expire, we will incur expenses and we may not be able to release the space on the same terms. Certain leases provide tenants with the right to terminate early if they pay a fee. While we have estimated our cost of renewing leases that expire in 1999, our estimates could be wrong. If we are unable to release space promptly, if the terms are significantly less favorable than anticipated or if the costs are higher, we may have to reduce our distributions to shareholders.

Tenant defaults and bankruptcies may reduce our cash flow and distributions. We may have difficulty in collecting from tenants in default, particularly if they declare bankruptcies. This could affect our cash flow and distributions to shareholders.

We may be adversely affected by significant competition among commercial properties. Many other commercial properties compete with our properties for tenants and we expect that new properties will be built in our markets. Also, we compete with other buyers, many of whom are larger than us, for attractive commercial properties. Therefore, we may not be able to grow as rapidly as we would like.

We may be adversely affected if losses on our properties are not covered by insurance. We carry insurance on our properties that we believe is comparable to the insurance carried by other operators for similar properties. However, we could suffer uninsured losses that adversely affect us or even result in loss of the property. We might still remain liable on any mortgage debt related to that property.

The illiquidity of our real estate investments may prevent us from adjusting our portfolio to respond to market changes. There may be delays and difficulties in selling real estate. Therefore, we cannot easily change our portfolio when economic conditions change. Also, tax laws limit a REIT's ability to sell properties held for less than four years.

We may be adversely affected by changes in laws. Increases in income and service taxes may reduce our cash flow and ability to make expected distributions to our shareholders. Our properties are also subject to various federal, state and local regulatory requirements, such as state and local fire and safety codes. If we fail to comply with these requirements, governmental authorities could fine us or courts could award damages against us. We believe our properties comply with all significant legal requirements. However, these requirements could change in a way that would reduce our cash flow and ability to make distributions to shareholders.

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We may incur significant environmental remediation costs. Under various federal, state and local environmental laws an owner or operator of real estate interests may have to clean spills or other releases of hazardous or toxic substances on or from a property. Certain environmental laws impose liability whether or not the owner knew of, or was responsible for, the presence of the hazardous or toxic substances. In some cases, liability may exceed the value of the property. The presence of toxic substances, or the failure to properly remedy any resulting contamination, may make it more difficult for the owner or operator to sell, lease or operate its property or to borrow money using its property as collateral. Future environmental laws may impose additional material liabilities on us.

In May 1998, we bought a property in Beaverton, Oregon known as Creekside Corporate Park. Under a consent order issued by the Oregon environmental agency, the current and past owners of the property are conducting an environmental remedial investigation of a property next to Creekside Corporate Park, which is owned by Mattel Corporation. We are not a party to the consent order. As part of the consent order, the Oregon environmental agency ordered the property owners to sample soil and groundwater on our property to determine the nature and extent of contamination resulting from past industrial operations at the Mattel property. We executed access agreements with the current and former property owners to allow access to our property to conduct the required sampling and testing. The sampling and testing is ongoing, and preliminary results from one area indicate that the contamination from the Mattel property may have migrated onto a portion of the Creekside Corporate Park that we own.

We believe that we bear no responsibility or liability for the contamination. If we are held responsible for any costs related to this matter, we believe that the party from whom the property was purchased will be responsible for any expenses or liabilities that we may incur as a result of this contamination.

We may be affected by the Americans with Disabilities Act. The Americans with Disabilities Act of 1990 requires that access and use by disabled persons of all public accommodations and commercial properties be facilitated. Existing commercial properties must be made accessible to disabled persons. While we have not estimated the cost of complying with this act, we do not believe the cost will be significant.

Our ability to control our properties may be adversely affected by ownership through partnerships and joint ventures.

We own most of our properties through our operating partnership. Our organizational documents do not limit our investment of funds with others in partnerships or joint ventures. This type of investment may present additional risks. For example, our partners may have interests that differ from ours or that conflict with ours, or our partners may become bankrupt.

We can change our business policies and increase our level of debt without shareholder approval.

Our board of directors establishes our investment, financing, distribution and our other business policies and may change these policies without shareholder approval. Our organizational documents do not limit our level of debt. A change in our policies or an increase in our level of debt could adversely affect our operations or the price of our common stock.

We can issue additional securities without shareholder approval.

We can issue preferred and common stock without shareholder approval. Holders of preferred stock have priority over holders of common stock, and the issuance of additional shares of common stock reduces the interest of existing holders in our company.

Increases in interest rates may adversely affect the market price of our common stock.

One of the factors that influences the market price of our common stock is the annual rate of distributions that we pay on our common stock, as compared with interest rates. An increase in interest rates may lead

4

purchasers of REIT shares to demand higher annual distribution rates, which could adversely affect the market price of our common stock.

Shares that become available for future sale may adversely affect the market price of our common stock.

Substantial sales of our common stock, or the perception that substantial sales may occur, could adversely affect the market price of our common stock. Certain of our shareholders hold significant numbers of shares of our common stock and, subject to compliance with applicable securities laws, could sell their shares.

We depend on key personnel.

We depend on our executive officers, including Ronald L. Havner, Jr., our chief executive officer and president, and Mary Jayne Howard, our chief operating officer and executive vice president. The loss of either of these executive officers could adversely affect our operations. We maintain no key person insurance on either of them.

ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission using a "shelf" registration process. Under this shelf process, we may sell from time to time up to $600,000,000 of our common stock, preferred stock, equity stock, depositary shares and warrants, in any combination. This prospectus provides a general description of the securities that we may offer. Each time we offer any of the types of securities described in this prospectus, we will prepare and distribute a prospectus supplement that will contain a description of the specific terms of the securities being offered and of the offering. The prospectus supplement may also supplement the information contained in this prospectus. You should read both this prospectus and the applicable prospectus supplement, together with the additional information described under the heading "Where You Can Find More Information," before purchasing any securities.

This prospectus may also be used in registered resales of common stock as described under "Plan of Distribution."

Unless otherwise indicated or unless the context requires otherwise, all references in this prospectus to "the Company," "we," "us," "our" and similar references mean PS Business Parks, Inc. and its subsidiaries, including PS Business Parks, L.P. All references in this prospectus to "our operating partnership" mean PS Business Parks, L.P.

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WHERE YOU CAN FIND MORE INFORMATION

We are subject to the reporting requirements of the Securities Exchange Act of 1934, and are required to file annual, quarterly and special reports with the Securities and Exchange Commission. You may read and copy any of these documents at the Commission's public reference rooms at Room 1024, Judiciary Plaza, 450 Fifth Street, N.W., Washington, D.C. 20549, and at the Commission's regional offices at Seven World Trade Center, 13th Floor, New York, New York 10048, and Citicorp Center, 500 West Madison Street, Suite 1400, Chicago, Illinois 60661-2511. You may telephone the Commission at 1-800-SEC-0330 for further information on the Commission's public reference facilities. The Commission also maintains a computer site on the World Wide Web (http://www.sec.gov) that contains the reports, proxy and information statements and other information that we and other registrants file electronically with the Commission. You can also inspect reports and other information we file at the offices of the American Stock Exchange, Inc., 86 Trinity Place, New York, New York 10006.

We have filed a registration statement on Form S-3, of which this prospectus is a part, with the Commission to register offers and sales of the securities described in this prospectus under the Securities Act of 1933. The registration statement contains additional information about us and the securities. You may read the registration statement and its exhibits without charge at the office of the Commission at 450 Fifth Street, N.W., Washington, D.C. 20549, or on the Commission's World Wide Web site, and you may obtain copies of it from the Commission at prescribed rates.

The Commission allows us to provide information about our business and other important information to you by "incorporating by reference" the information we file with the Commission, which means that we can disclose that information to you by referring in this prospectus to the documents we file with the Commission. Under the Commission's regulations, any statement contained in a document incorporated by reference in this prospectus is automatically updated and superseded by any information contained in this prospectus, or in any subsequently filed document of the types described below.

We incorporate into this prospectus by reference the following documents filed by us with the Commission, each of which should be considered an important part of this prospectus:

         SEC Filing (File No. 1-10709)            Period Covered or Date of Filing
         -----------------------------            --------------------------------
Annual Report on Form 10-K...................... Year ended December 31, 1998
Quarterly Report on Form 10-Q................... Quarter ended March 31, 1999
Current Report on Form 8-K...................... Dated April 28, 1999
Description of our common stock contained in
 Registration Statement on Form 8-A, as
 supplemented by the description of our common
 stock contained in this prospectus............. Effective March 15, 1991
All subsequent documents filed by us under
 Sections 13(a), 13(c), 14 or 15(d) of the
 Exchange Act of 1934........................... After the date of this prospectus
                                                 and before the termination of the
                                                 offering

You may request a copy of each of our filings at no cost, by writing or telephoning us at the following address, telephone or facsimile number:

Investor Services Department
PS Business Parks, Inc.
701 Western Avenue
Glendale, California 91201-2397
Telephone: (800) 807-3055
(800) 421-2856
(818) 244-8080
Facsimile: (818) 241-0627

Exhibits to a document will not be provided unless they are specifically incorporated by reference in that document.

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FORWARD-LOOKING STATEMENTS

Some of the information included or incorporated by reference in this prospectus contains forward-looking statements, such as those pertaining to our portfolio performance and future results of operations, market conditions and prospects. The pro forma financial statements and other pro forma information incorporated by reference in this prospectus also contain forward- looking statements. You can identify forward-looking statements by their use of forward-looking terminology such as "believes," "expects," "may," "will," "should," "seeks," "intends," "plans," "pro forma," "estimates" or "anticipates" or the negative of these words and phrases or similar words or phrases. Discussion of strategy, plans or intentions also include forward- looking statements.

Forward-looking statements inherently involve risks and uncertainties and you should not rely on them as predictions of future events. The factors described above under the heading "Risk Factors," as well as changes in the commercial real estate market and the general economy, could cause future events and actual results to differ materially from those set forth or contemplated in the forward-looking statements.

THE COMPANY

We are a self-advised and self-managed real estate investment trust or REIT that acquires, develops, owns and operates commercial properties. We are the sole general partner of our operating partnership, PS Business Parks, L.P., through which we conduct most of our activities. At March 31, 1999, we owned approximately 73% of our operating partnership with substantially all of the balance owned by Public Storage, Inc.

In a March 1998 merger with American Office Park Properties, Inc., we acquired the commercial property business previously operated by Public Storage and were renamed "PS Business Parks, Inc." At March 31, 1999, we owned 114 commercial properties in 11 states containing approximately 11.3 million square feet of space.

We elected to be taxed as a REIT beginning with our 1990 taxable year. To the extent that we continue to qualify as a REIT, we will not be taxed, with certain limited exceptions, on the net income that we distribute currently to our shareholders. We were incorporated in California in 1990. Our principal executive offices are located at 701 Western Avenue, Glendale, California 91201-2397. Our telephone number is (818) 244-8080.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities described in this prospectus for the acquisition of commercial properties, repayment of our outstanding debt and for general business purposes. Pending their use, we may invest the net proceeds in short-term, interest bearing securities.

RATIO OF EARNINGS TO FIXED CHARGES

We compute our ratio of earnings to combined fixed charges and preferred stock dividends by dividing our earnings by our fixed charges. Earnings consists of net income before minority interest in income, loss on early extinguishment of debt and gain on disposition of real estate plus fixed charges less the portion of minority interest in income which does not contribute to fixed charges. In computing our ratio for periods prior to March 17, 1998, we used the operations and fixed charges of American Office Park Properties, Inc., our predecessor for accounting and financial reporting purposes.

                               For the Three
                               Months Ended
                                 March 31,   For the Year Ended December 31,
                               ------------- ------------------------------
                                1999   1998  1998    1997    1996 1995 1994
                               ------ ------ ----- --------- ---- ---- ----
Ratio of earnings to combined
 fixed charges and preferred
 stock dividends..............  12.17  29.92 16.34 12,403.00 N/A  N/A  N/A

N/A--not applicable as we did not have any fixed charges in this period.

DESCRIPTION OF COMMON STOCK

We are authorized to issue 100,000,000 shares of common stock. At April 30, 1999, we had outstanding 23,637,410 shares of common stock (exclusive of a total of 7,903,666 shares issuable upon exchange of interests in our operating partnership and shares subject to options).

Common Stock

The following description of our common stock sets forth certain general terms and provisions of the common stock to which any prospectus supplement may relate, including a prospectus supplement providing that common stock will be issuable upon conversion of preferred stock or upon the exercise of warrants. The statements below describing our common stock are in all respects subject to and qualified in their entirety by reference to the applicable provisions of our articles of incorporation and bylaws.

Holders of our common stock will be entitled to receive dividends when, as and if declared by our board of directors, out of funds legally available therefor. Payment and declaration of dividends on our common stock and purchases of shares of common stock by us will be subject to certain restrictions if we fail to pay dividends on outstanding preferred stock. See "Description of Preferred Stock." Upon any liquidation, dissolution or winding up of the Company, holders of common stock will be entitled to share equally and ratably in any assets available for distribution to them, after payment or provision for payment of the debts and our other liabilities and the preferential amounts owing with respect to any of our outstanding preferred stock. Holders of our common stock have no preemptive rights, except such as have been provided to certain of our shareholders by contract, which means public shareholders have no right to acquire any additional shares of common stock that we may issue at a later date.

Each outstanding share of our common stock entitles the holder to one vote on all matters presented to our holders for a vote, with the exception that they have cumulative voting rights with respect to the election of our board of directors, in accordance with California law. Cumulative voting means that each holder of our common stock is entitled to cast as many votes as there are directors to be elected multiplied by the number of shares

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registered in his or her name. A holder of our common stock may cumulate the votes for directors by casting all of the votes for one candidate or by distributing the votes among as many candidates as he or she chooses. The outstanding shares of our common stock are, and additional shares of common stock will be, when issued, fully paid and nonassessable.

The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock or our equity stock which we may designate and issue in the future. See "Description of Preferred Stock" and "Description of Equity Stock."

Ownership Limitations

For us to qualify as a REIT under the Code, no more than 50% in value of our outstanding shares of capital stock may be owned, directly or constructively under the applicable attribution rules of the Code, by five or fewer individuals (as defined in the Code to include certain entities) during the last half of a taxable year. In order to maintain our qualification as a REIT, our articles of incorporation provide certain restrictions on the shares of capital stock that any shareholder may own.

Our articles of incorporation provide that, subject to certain exceptions, no holder may own, or be deemed to own by virtue of the attribution provisions of the Code, more than (A) 7.0% of the outstanding shares of our common stock and (B) 9.9% of the outstanding shares of each class or series of shares of our preferred stock or equity stock and that all shares of stock be imprinted with a legend setting forth that restriction. Our articles of incorporation provide, however, that no person shall be deemed to exceed the ownership limit solely by reason of the beneficial ownership of shares of any class of stock to the extent that such shares of stock were beneficially owned by such person (including Public Storage) upon completion of, and after giving effect to, the merger with American Office Park Properties. Thus, this limitation does not affect the ownership of common stock held by Public Storage and certain other shareholders at the time of the merger. Furthermore, the limitation does not apply with respect to shares of stock deemed to be owned by a person as a result of such person's ownership of shares of Public Storage (however, such ownership will be taken into account in determining whether a subsequent acquisition or transfer of our shares (but not Public Storage) violates the ownership limit). The ownership limitation is intended to assist in preserving our REIT status in view of Public Storage's substantial ownership interest in us and the Hughes family's substantial ownership interest in Public Storage. There can be no assurance, however, that such ownership limit will enable us to satisfy the requirement that a REIT not be "closely held" within the meaning of Section 856(h) of the Code for any given taxable year, in part as a result of the provision described above providing that the ownership limitation generally does not apply to our shares deemed to be owned as a result of a person's ownership of shares of Public Storage.

Our articles of incorporation provide that our board of directors, in its sole and absolute discretion, may grant exceptions to the ownership limits, so long as (A) our board has determined that we would not be "closely held" within the meaning of Section 856(h) of the Code (without regard to whether the event in question takes place during the second half of a taxable year) and would not otherwise fail to qualify as a REIT, after giving effect to an acquisition by an excepted person of beneficial ownership of the maximum amount of capital stock permitted as a result of the exception to be granted, and taking into account the existing and permitted ownership by other persons of stock (taking into account any other exceptions granted) and (B) the excepted persons provide to our board such representations and undertakings as our board may require. In any case, no holder may own or acquire, either directly, indirectly or constructively under the applicable attribution rules of the Code, any shares of any class of capital stock if such ownership or acquisition (i) would cause more than 50% in value of outstanding capital stock to be owned, either directly or constructively, under the applicable attribution rules of the Code, by five or fewer individuals (as defined in the Code to include certain tax-exempt entities, other than, in general, qualified domestic pension funds), (ii) would result in the Company's stock being beneficially owned by less than 100 persons (determined without reference to any rules of attribution), or (iii) would otherwise result in our failing to qualify as a REIT.

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Our articles of incorporation generally provide that if any holder of capital stock purports to transfer shares to a person or there is a change in our capital structure, and either the transfer or the change in capital structure would result in our failing to qualify as a REIT, or such transfer or the change in capital structure would cause the transferee to hold shares in excess of the applicable ownership limit, then the shares causing the violation will be automatically transferred to a trust for the benefit of a designated charitable beneficiary. The purported transferee of those shares will have no right to receive dividends or other distributions with respect to them and will have no right to vote the shares. Any dividends or other distributions paid to such purported transferee prior to the discovery by us that the shares have been transferred to a trust will be paid to the trustee of the trust for the benefit of the charitable beneficiary upon demand. The trustee will designate a transferee of those shares so long as the shares would not violate the restrictions on ownership or transfer in the articles of incorporation in the hands of the designated transferee. Upon the sale of such shares, the purported transferee will receive out of any proceeds remaining after payment of expenses of the charitable trust and us the lesser of (A)(i) the price per share such purported transferee paid for the stock in the purported transfer that resulted in the transfer of the shares to the trust, or (ii) if the transfer or other event that resulted in the transfer of the shares to the trust was not a transaction in which the purported transferee gave full value for such shares, a price per share equal to the market price on the date of the purported transfer or other event that resulted in the transfer of the shares to the trust and (B) the price per share received by the trustee from the sale or other disposition of the shares held in the trust. Each purported transferee shall be deemed to have waived any claims such purported transferee may have against the trustee and us arising from the disposition of the shares, except for claims arising from the trustee's or our gross negligence, willful misconduct, or failure to make payments when required by the articles of incorporation.

DESCRIPTION OF PREFERRED STOCK

We are authorized to issue 50,000,000 shares of preferred stock. At April 30, 1999, we had 2,200 outstanding shares of preferred stock (represented by 2,200,000 depositary shares) and 510,000 shares reserved for issuance. Our articles of incorporation provide that the preferred stock may be issued from time to time in one or more series and give our board of directors broad authority to fix the dividend and distribution rights, conversion and voting rights, if any, redemption provisions and liquidation preferences of each series of preferred stock. Holders of preferred stock have no preemptive rights. The preferred stock will be, when issued, fully paid and nonassessable.

Although the issuance of preferred stock with special voting rights (or common stock) could be used to deter attempts to obtain control of us in transactions not approved by our board of directors, we have no present intention to issue stock for that purpose.

Outstanding Preferred Stock

At April 30, 1999, we had outstanding a series of preferred stock. It
(1) has a stated value of $25 per depositary share, (2) in preference to the holders of shares of our common stock and any other capital stock ranking junior to the preferred stock as to payment of dividends, provides for cumulative quarterly dividends of 9 1/4% of the stated value and (3) is subject to redemption, in whole or in part, at our option at a cash redemption price of $25 per depositary share, plus accrued and unpaid dividends, on and after April 30, 2004.

In the event of our voluntary or involuntary liquidation, dissolution or winding up, the holders of the preferred stock will be entitled to receive out of our assets available for distribution to shareholders, before any distribution of assets is made to holders of our common stock or any other shares of capital stock ranking as to such distributions junior to the preferred stock, liquidating distributions in the amount of $25 per depositary share, plus all accrued and unpaid dividends.

Except as expressly required by law and in certain other limited circumstances, holders of the preferred stock are not entitled to vote. The consent of holders of at least 66 2/3% of the outstanding shares of the preferred stock (and any other series of preferred stock ranking on a parity therewith), voting as a single class, is required to authorize another class of shares senior to the preferred stock.

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Ownership Limitations

For a discussion of the ownership limitations that apply to preferred stock, see "Description of Common Stock--Ownership Limitations."

Future Series of Preferred Stock

The following description of preferred stock sets forth certain general terms and provisions of the preferred stock to which any prospectus supplement may relate. The statements below describing the preferred stock are in all respects subject to and qualified in their entirety by reference to the applicable provisions of our articles of incorporation (including the applicable form of certificate of determination) and bylaws.

Reference is made to the prospectus supplement relating to the preferred stock offered thereby for specific terms, including, where applicable, the following: (1) the title and stated value of such preferred stock; (2) the number of shares of such preferred stock offered, the liquidation preference per share and the offering price of such preferred stock; (3) the dividend rate(s), period(s) and/or payment date(s) or method(s) of calculation applicable to such preferred stock; (4) the date from which dividends on such preferred stock shall accumulate, if applicable; (5) the provision for a sinking fund, if any, for such preferred stock; (6) the provision for redemption, if applicable, of such preferred stock; (7) any listing of such preferred stock on any securities exchange; (8) the terms and conditions, if applicable, upon which such preferred stock will be convertible into common stock, including the conversion price (or manner of calculation); (9) the voting rights, if any, of such preferred stock; (10) any other specific terms, preferences, rights, limitations or restrictions of such preferred stock; (11) the relative ranking and preferences of such preferred stock as to dividend rights and rights upon liquidation, dissolution or winding up of our affairs; and (12) any limitations on issuance of any series of preferred stock ranking senior to or on a parity with such series of preferred stock as to dividend rights and rights upon liquidation, dissolution or winding up of our affairs.

Ranking. The ranking of the preferred stock is set forth in the applicable prospectus supplement. Unless otherwise specified in the applicable prospectus supplement, such preferred stock will, with respect to dividend rights and rights upon liquidation, dissolution or winding up of our affairs, rank (i) senior to the common stock, any additional class of common stock and any series of preferred stock expressly made junior to such preferred stock; (ii) on a parity with all preferred stock previously issued by us the terms of which specifically provide that such preferred stock rank on a parity with the preferred stock offered hereby; and (iii) junior to all preferred stock previously issued by us the terms of which specifically provide that such preferred stock rank senior to the preferred stock offered hereby.

Dividends. Holders of shares of the preferred stock of each series offered hereby will be entitled to receive, when, as and if declared by our board of directors, out of our assets legally available for payment, cash dividends at such rates and on such dates as will be set forth in the applicable prospectus supplement. Each such dividend shall be payable to holders of record as they appear on the stock transfer books of the Company on such record dates as shall be fixed by our board of directors.

Dividends on any series of the preferred stock offered hereby may be cumulative or non-cumulative, as provided in the applicable prospectus supplement. Dividends, if cumulative, will be cumulative from and after the date set forth in the applicable prospectus supplement. If our board of directors fails to declare a dividend payable on a dividend payment date on any series of the preferred stock for which dividends are noncumulative, then the holders of such series of the preferred stock will have no right to receive a dividend in respect of the dividend period ending on such dividend payment date, and we will have no obligation to pay the dividend accrued for such period, whether or not dividends on such series are declared payable on any future dividend payment date.

No dividends (other than in common stock or other capital stock ranking junior to the preferred stock of any series as to dividends and upon liquidation) will be declared or paid or set aside for payment (nor will any other distribution be declared or made upon the common stock, or any other capital stock of us ranking junior to

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or on a parity with the preferred stock of such series as to dividends or upon liquidation), nor will any common stock or any other of our capital stock ranking junior to or on a parity with the preferred stock of such series as to dividends or upon liquidation be redeemed, purchased or otherwise acquired for any consideration (or any moneys be paid to or made available for a sinking fund for the redemption of any shares of any such stock) by us (except by conversion into or exchange for other capital stock of us ranking junior to the preferred stock of such series as to dividends and upon liquidation) unless (i) if such series of preferred stock has a cumulative dividend, full cumulative dividends on the preferred stock of such series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for all past dividend periods and the then current dividend period, and (ii) if such series of preferred stock does not have a cumulative dividend, full dividends on the preferred stock of such series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for the then current dividend period.

Any dividend payment made on shares of a series of cumulative preferred stock offered hereby will first be credited against the earliest accrued but unpaid dividend due with respect to shares of such series which remains payable.

Redemption. If so provided in the applicable prospectus supplement, the shares of preferred stock will be subject to mandatory redemption or redemption at our option, in whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

The prospectus supplement relating to a series of preferred stock offered hereby that is subject to mandatory redemption will specify the number of shares of such preferred stock that will be redeemed by us in each year commencing after a date to be specified, at a redemption price per share to be specified, together with an amount equal to all accrued and unpaid dividends thereon (which will not, if such preferred stock does not have a cumulative dividend, include any accumulation in respect of unpaid dividends for prior dividend periods) to the date of redemption. The redemption price may be payable in cash, securities or other property, as specified in the applicable prospectus supplement.

Notwithstanding the foregoing, no shares of any series of preferred stock offered hereby will be redeemed and we will not purchase or otherwise acquire directly or indirectly any shares of preferred stock of such series (except by conversion into or exchange for capital stock of us ranking junior to the preferred stock of such series as to dividends and upon liquidation) unless all outstanding shares of preferred stock of such series are simultaneously redeemed unless, in each case, (i) if such series of preferred stock has a cumulative dividend, full cumulative dividends on the preferred stock of such series will have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for all past dividend periods and the then current dividend period and (ii) if such series of preferred stock does not have a cumulative dividend, full dividends on the preferred stock of such series have been or contemporaneously are declared and paid or declared and a sum sufficient for the payment thereof set apart for payment for the then current dividend period; provided, however, that the foregoing shall not prevent the purchase or acquisition of shares of preferred stock of such series pursuant to a purchase or exchange offer made on the same terms to holders of all outstanding shares of preferred stock of such series.

If fewer than all of the outstanding shares of preferred stock of any series offered hereby are to be redeemed, the number of shares to be redeemed will be determined by us and such shares may be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held by such holders (with adjustments to avoid redemption of fractional shares) or any other equitable method determined by us.

Notice of redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each holder of record of preferred stock of any series to be redeemed at the address shown on our stock transfer books. Each notice will state: (i) the redemption date; (ii) the number of shares and series of the preferred stock to be redeemed; (iii) the redemption price; (iv) the place or places where certificates for such preferred stock are to be surrendered for payment of the redemption price; (v) that dividends on the shares to be redeemed

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will cease to accrue on such redemption date; and (vi) the date upon which the holder's conversion rights, if any, as to such shares shall terminate. If fewer than all the shares of preferred stock of any series are to be redeemed, the notice mailed to each such holder thereof shall also specify the number of shares of preferred stock to be redeemed from each such holder and, upon redemption, a new certificate shall be issued representing the unredeemed shares without cost to the holder thereof. In order to facilitate the redemption of shares of preferred stock, our board of directors may fix a record date for the determination of shares of preferred stock to be redeemed, such record date to be not less than 30 or more than 60 days prior to the date fixed for such redemption.

Notice having been given as provided above, from and after the date specified therein as the date of redemption, unless we default in providing funds for the payment of the redemption price on such date, all dividends on the preferred stock called for redemption will cease. From and after the redemption date, unless we so default, all rights of the holders of the preferred stock as our shareholders, except the right to receive the redemption price (but without interest), will cease.

Subject to applicable law and the limitation on purchases when dividends on preferred stock are in arrears, we may, at any time and from time to time, purchase any shares of preferred stock in the open market, by tender or by private agreement.

Liquidation Preference. Upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, then, before any distribution or payment shall be made to the holders of any common stock or any other class or series of our capital stock ranking junior to any series of the preferred stock in the distribution of assets upon our liquidation, dissolution or winding up, the holders of such series of preferred stock will be entitled to receive out of our assets legally available for distribution to shareholders liquidating distributions in the amount of the liquidation preference per share (set forth in the applicable prospectus supplement), plus an amount equal to all dividends accrued and unpaid thereon (which shall not include any accumulation in respect of unpaid dividends for prior dividend periods if such preferred stock does not have a cumulative dividend). After payment of the full amount of the liquidating distributions to which they are entitled, the holders of preferred stock will have no right or claim to any of our remaining assets. In the event that, upon any such voluntary or involuntary liquidation, dissolution or winding up, our legally available assets are insufficient to pay the amount of the liquidating distributions on all outstanding shares of any series of preferred stock and the corresponding amounts payable on all shares of other classes or series of our capital stock ranking on a parity with the preferred stock in the distribution of assets upon liquidation, dissolution or winding up, then the holders of such series of preferred stock and all other such classes or series of capital stock shall share ratably in any such distribution of assets in proportion to the full liquidating distributions to which they would otherwise be respectively entitled.

If liquidating distributions shall have been made in full to all holders of preferred stock, our remaining assets will be distributed among the holders of any other classes or series of capital stock ranking junior to such series of preferred stock upon liquidation, dissolution or winding up, according to their respective rights and preferences and in each case according to their respective number of shares. For such purposes, our consolidation or merger with or into any other corporation, or the sale, lease, transfer or conveyance of all or substantially all of our property or business will not be deemed to constitute a liquidation, dissolution or winding up.

Voting Rights. Holders of the preferred stock offered hereby will not have any voting rights, except as set forth below or as otherwise expressly required by law or as indicated in the applicable prospectus supplement.

If the equivalent of six quarterly dividends payable on any series of preferred stock are in default (whether or not declared or consecutive), the holders of all such series of preferred stock, voting as a single class with all other series of preferred stock upon which similar voting rights have been conferred and are exercisable, will be entitled to elect two additional directors until all dividends in default have been paid or declared and set apart for payment.

Such right to vote separately to elect directors shall, when vested, be subject, always, to the same provisions for vesting of such right to elect directors separately in the case of future dividend defaults. At any time when

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such right to elect directors separately shall have so vested, we may, and upon the written request of the holders of record of not less than 20% of our total number of preferred shares then outstanding shall, call a special meeting of shareholders for the election of directors. In the case of such a written request, such special meeting shall be held within 90 days after the delivery of such request and, in either case, at the place and upon the notice provided by law and in the bylaws, provided that we will not be required to call such a special meeting if such request is received less than 120 days before the date fixed for the next ensuing annual meeting of shareholders, and the holders of all classes of outstanding preferred stock are offered the opportunity to elect such directors (or fill any vacancy) at such annual meeting of shareholders. Directors so elected will serve until the next annual meeting of shareholders or until their respective successors are elected and qualify. If, prior to the end of the term of any director so elected, a vacancy in the office of such director shall occur, during the continuance of a default by reason of death, resignation, or disability, such vacancy shall be filled for the unexpired term of such former director by the appointment of a new director by the remaining director or directors so elected.

The affirmative vote or consent of the holders of at least a majority of the outstanding shares of each series of preferred stock will be required to amend or repeal any provision of or add any provision to, our articles of incorporation, including the certificate of determination, if such action would materially and adversely alter or change the rights, preferences or privileges of such series of preferred stock.

No consent or approval of the holders of any series of preferred stock offered hereby will be required for the issuance from our authorized but unissued preferred stock of other shares of any series of preferred stock ranking on a parity with or junior to such series of preferred stock, or senior to a series of preferred stock expressly made junior to other series of preferred stock as to payment of dividends and distribution of assets, including other shares of such series of preferred stock.

The foregoing voting provisions will not apply if, at or prior to the time when the act with respect to which such vote would otherwise be required shall be effected, all outstanding shares of such series of preferred stock had been redeemed or called for redemption upon proper notice and sufficient funds had been deposited in trust to effect such redemption.

Conversion Rights. The terms and conditions, if any, upon which shares of any series of preferred stock offered hereby are convertible into common stock will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of common stock into which the preferred stock is convertible, the conversion price (or manner of calculation thereof), the conversion period, provisions as to whether conversion will be at our option or at the option of the holders of the preferred stock or automatically upon the occurrence of certain events, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of such preferred stock.

DESCRIPTION OF EQUITY STOCK

We are authorized to issue 100,000,000 shares of equity stock. At April 30, 1999, we had no outstanding shares of equity stock. Our articles of incorporation provide that the equity stock may be issued from time to time in one or more series and give our board of directors broad authority to fix the dividend and distribution rights, conversion and voting rights, redemption provisions and liquidation rights of each series of equity stocks. Holders of equity stock have no preemptive rights. The shares of equity stock will be, when issued, fully paid and nonassessable.

The issuance of equity stock with special voting rights (or common stock) could be used to deter attempts by a single shareholder or group of shareholders to obtain control of us in transactions not approved by our board of directors. We have no intention to issue the equity stock (or common stock) for such purposes.

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Ownership Limitations

For a discussion of the ownership limitations that apply to equity stock, see "Description of Common Stock--Ownership Limitations."

Terms of Equity Stock

The following description of equity stock sets forth certain general terms and provisions of the equity stock to which any prospectus supplement may relate. The statements below describing the equity stock are in all respects subject to and qualified in their entirety by reference to the applicable provisions of our articles of incorporation (including the applicable form of certificate of determination) and bylaws.

Reference is made to the prospectus supplement relating to the equity stock offered thereby for specific terms, including, where applicable, the following: (1) the designation of such equity stock; (2) the number of shares of such equity stock offered, the liquidation rights and the offering price of such equity stock; (3) the dividend rate(s), period(s) and/or payment date(s) or method(s) of calculation applicable to such equity stock; (4) the provision for redemption, if applicable, of such equity stock; (5) any listing of such equity stock on any securities exchange; (6) the terms and conditions, if applicable, upon which such equity stock will be convertible into common stock, including the conversion price (or manner of calculation thereof); (7) the voting rights, if any, of such equity stock; (8) any other specific terms, rights, limitations or restrictions of such equity stock; and (9) the relative ranking of such equity stock as to dividend rights and rights upon liquidation, dissolution or winding up of our affairs.

Ranking. The ranking of the equity stock is set forth in the applicable prospectus supplement. Unless otherwise specified in the applicable prospectus supplement, such equity stock will, with respect to dividend rights and rights upon liquidation, dissolution or winding up of our affairs, rank on a parity with the common stock.

Dividends. Holders of shares of the equity stock of each series offered hereby shall be entitled to receive, when, as and if declared by our board of directors, out of our assets legally available for payment, cash dividends at such rates and on such dates as will be set forth in the applicable prospectus supplement. Each such dividend shall be payable to holders of record as they appear on our stock transfer books on such record dates as shall be fixed by our board of directors. Unless otherwise specified in the applicable prospectus supplement, dividends on such equity stock will be non-cumulative.

Redemption. If so provided in the applicable prospectus supplement, the shares of equity stock will be subject to mandatory redemption or redemption at our option, in whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

The prospectus supplement relating to a series of equity stock offered hereby that is subject to mandatory redemption will specify the number of shares of such equity stock that we redeem in each year commencing after a date to be specified, at a redemption price per share to be specified, together with an amount equal to all accrued and unpaid dividends thereon (which shall not, if such equity stock does not have a cumulative dividend, include any accumulation in respect of unpaid dividends for prior dividend periods) to the date of redemption. The redemption price may be payable in cash, securities or other property, as specified in the applicable prospectus supplement.

If fewer than all of the outstanding shares of equity stock of any series offered hereby are to be redeemed, the number of shares to be redeemed will be determined by us and such shares may be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held by such holders (with adjustments to avoid redemption of fractional shares) or any other equitable method determined by us.

Notice of redemption will be mailed at least 30 days but not more than 60 days before the redemption date to each holder of record of equity stock of any series to be redeemed at the address shown on our stock transfer

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books. Each notice shall state: (i) the redemption date; (ii) the number of shares and series of the equity stock to be redeemed; (iii) the redemption price; (iv) the place or places where certificates for such equity stock are to be surrendered for payment of the redemption price; (v) that dividends on the shares to be redeemed will cease to accrue on such redemption date; and
(vi) the date upon which the holder's conversion rights, if any, as to such shares shall terminate. If fewer than all the shares of equity stock of any series are to be redeemed, the notice mailed to each such holder thereof shall also specify the number of shares of equity stock to be redeemed from each such holder and, upon redemption, a new certificate shall be issued representing the unredeemed shares without cost to the holder thereof. In order to facilitate the redemption of shares of equity stock, our board of directors may fix a record date for the determination of shares of equity stock to be redeemed, such record date to be not less than 30 or more than 60 days prior to the date fixed for such redemption.

Notice having been given as provided above, from and after the date specified therein as the date of redemption, unless we default in providing funds for the payment of the redemption price on such date, all dividends on the Equity Stock called for redemption will cease. From and after the redemption date, unless we so default, all rights of the holders of the equity stock as our shareholders, except the right to receive the redemption price (but without interest), will cease.

Liquidation Rights. If we voluntarily or involuntarily liquidate, dissolve or wind-up our affairs, then, before any distribution or payment may be made to the holders of the equity stock or any other class or series of our capital stock ranking junior to any series of the preferred stock in the distribution of assets upon our liquidation, dissolution or winding up, the holders of such series of preferred stock will be entitled to receive out of our assets legally available for distribution to shareholders liquidating distributions in the amount of the liquidation preference per share, plus an amount equal to all dividends accrued and unpaid thereon (which shall not include any accumulation in respect of unpaid dividends for prior dividend periods if such preferred stock does not have a cumulative dividend). After payment of the full amount of the liquidating distributions to which they are entitled, the holders of Preferred Stock will have no right or claim to any of our remaining assets. If we voluntarily or involuntarily liquidate, dissolve or wind-up our affairs and our legally available assets are insufficient to pay the amount of the liquidating distributions on all outstanding shares of any series of preferred stock and the corresponding amounts payable on all shares of other classes or series of our capital stock ranking on a parity with the preferred stock in the distribution of assets upon liquidation, dissolution or winding up, then the holders of such series of preferred stock and all other such classes or series of capital stock shall share ratably in any such distribution of assets in proportion to the full liquidating distributions to which they would otherwise be respectively entitled.

If liquidating distributions have been made in full to all holders of preferred stock, our remaining assets will be distributed among the holders of any other classes or series of capital stock ranking junior to such series of preferred stock upon liquidation, dissolution or winding up, including the equity stock, according to their respective rights and in each case according to their respective number of shares. For such purposes, our consolidation or merger with or into any other corporation, or the sale, lease, transfer or conveyance of all or substantially all of our property or business, will not be deemed to constitute a liquidation, dissolution or winding up.

Unless otherwise specified in the applicable prospectus supplement, upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, holders of the equity stock will rank on a parity with the holders of the common stock, subject to any maximum or minimum distribution to holders of equity stock specified in such prospectus supplement.

Voting Rights. Unless otherwise specified in the applicable prospectus supplement, holders of the equity stock will have the same voting rights as holders of the common stock.

No consent or approval of the holders of any series of equity stock will be required for the issuance from our authorized but unissued equity stock of other shares of any series of equity stock including shares of such series of equity stock.

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Conversion Rights. The terms and conditions, if any, upon which shares of any series of equity stock offered hereby are convertible into common stock will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of common stock into which the equity stock is convertible, the conversion price (or manner of calculation), the conversion period, provisions as to whether conversion will be at our option or at the option of the holders of the equity stock or automatically upon the occurrence of certain events, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of such equity stock.

DESCRIPTION OF THE DEPOSITARY SHARES

We may, at our option, elect to offer depositary shares rather than full shares of preferred stock or equity stock. In the event such option is exercised, each of the depositary shares will represent ownership of and entitlement to all rights and preferences of a fraction of a share of preferred stock or equity stock of a specified series (including dividend, voting, redemption and liquidation rights). The applicable fraction will be specified in the prospectus supplement. The shares of preferred stock or equity stock represented by the depositary shares will be deposited with a depositary named in the applicable prospectus supplement, under a deposit agreement, among the depositary, the holders of the depositary receipts and us. Depositary receipts, which are certificates evidencing depositary shares, will be delivered to those persons purchasing depositary shares in the offering. The depositary will be the transfer agent, registrar and dividend disbursing agent for the depositary shares. Holders of depositary receipts agree to be bound by the deposit agreement, which requires holders to take certain actions such as filing proof of residence and paying certain charges.

The summary of terms of the depositary shares contained in this prospectus does not purport to be complete and is subject to, and qualified in its entirety by, the provisions of the deposit agreement, our articles of incorporation and the form of certificate of determination for the applicable series of preferred stock or equity stock.

Dividends

The depositary will distribute all cash dividends or other cash distributions received in respect of the series of preferred stock represented by the depositary shares to the record holders of depositary receipts in proportion to the number of depositary shares owned by such holders on the relevant record date, which will be the same date as the record date fixed by us for the applicable series of preferred stock or equity stock. The depositary, however, will distribute only such amount as can be distributed without attributing to any depositary share a fraction of one cent, and any balance not so distributed will be added to and treated as part of the next sum received by the depositary for distribution to record holders of depositary receipts then outstanding.

In the event of a distribution other than in cash, the depositary will distribute property received by it to the record holders of depositary receipts entitled thereto, in proportion, as nearly as may be practicable, to the number of depositary shares owned by such holders on the relevant record date, unless the depositary determines (after consultation with us) that it is not feasible to make such distribution, in which case the depositary may (with our approval) adopt any other method for such distribution as it deems equitable and appropriate, including the sale of such property (at such place or places and upon such terms as it may deem equitable and appropriate) and distribution of the net proceeds from such sale to such holders.

Liquidation Rights

In the event of the liquidation, dissolution or winding up of our affairs, whether voluntary or involuntary, the holders of each depositary share will be entitled to the fraction of the liquidation amount accorded each share of the applicable series of preferred stock or equity stock, as set forth in the prospectus supplement.

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Redemption

If the series of preferred stock represented by the applicable series of depositary shares is redeemable, such depositary shares will be redeemed from the proceeds received by the depositary resulting from the redemption, in whole or in part, of preferred stock or equity stock held by the depositary. Whenever we redeem any preferred stock or equity stock held by the depositary, the depositary will redeem as of the same redemption date the number of depositary shares representing the preferred stock or equity stock so redeemed. The depositary will mail the notice of redemption promptly upon receipt of such notice from us and not less than 30 nor more than 60 days prior to the date fixed for redemption of the preferred stock or equity stock and the depositary shares to the record holders of the depositary receipts.

Conversion

If the series of preferred stock or equity stock represented by the applicable series of depositary shares is convertible into a different class of our securities, the depositary shares will be also be convertible on the terms described in the applicable prospectus supplement.

Voting

Promptly upon receipt of notice of any meeting at which the holders of the series of preferred stock or equity stock represented by the applicable series of depositary shares are entitled to vote, the depositary will mail the information contained in such notice of meeting to the record holders of the depositary receipts as of the record date for such meeting. Each such record holder of depositary receipts will be entitled to instruct the depositary as to the exercise of the voting rights pertaining to the number of shares of preferred stock or equity stock represented by such record holder's depositary shares. The depositary will endeavor, insofar as practicable, to vote such preferred stock or equity stock represented by such depositary shares in accordance with such instructions, and we will agree to take all action which may be deemed necessary by the depositary in order to enable the depositary to do so. The depositary will abstain from voting any of the preferred stock or equity stock to the extent that it does not receive specific instructions from the holders of depositary receipts.

Withdrawal of Preferred Stock

Upon surrender of depositary receipts at the principal office of the depositary, upon payment of any unpaid amount due the depositary, and subject to the terms of the deposit agreement, the owner of the depositary shares evidenced thereby is entitled to delivery of the number of whole shares of preferred stock or equity stock and all money and other property, if any, represented by such depositary shares. Partial shares of preferred stock or equity stock will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred stock or equity stock to be withdrawn, the depositary will deliver to such holder at the same time a new depositary receipt evidencing such excess number of depositary shares. Holders of preferred stock or equity stock thus withdrawn will not thereafter be entitled to deposit such shares under the deposit agreement or to receive depositary receipts evidencing depositary shares therefor.

Amendment and Termination of Deposit Agreement

The form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may at any time and from time to time be amended by agreement between the Depositary and us. However, any amendment which materially and adversely alters the rights of the holders (other than any change in fees) of depositary shares will not be effective unless such amendment has been approved by at least a majority of the depositary shares then outstanding. No such amendment may impair the right, subject to the terms of the deposit agreement, of any owner of any depositary shares to surrender the depositary receipt evidencing such depositary shares with instructions to the depositary to deliver to the holder the preferred stock and all money and other property, if any, represented thereby, except in order to comply with mandatory provisions of applicable law. The deposit agreement may be terminated by the depositary or us only if (i) all outstanding depositary shares

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have been redeemed or (ii) there has been a final distribution in respect of the preferred stock or equity stock in connection with our liquidation, dissolution or winding up and such distribution has been made to all the holders of depositary shares.

Charges of Depositary

We will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We will pay charges of the depositary in connection with the initial deposit of the preferred stock or equity stock and the initial issuance of the depositary shares, and redemption of the preferred stock or equity stock and all withdrawals of preferred stock or equity stock by owners of depositary shares. Holders of depositary receipts will pay transfer, income and other taxes and governmental charges and certain other charges as are provided in the deposit agreement to be for their accounts. In certain circumstances, the depositary may refuse to transfer depositary shares, may withhold dividends and distributions and sell the depositary shares evidenced by such depositary receipt if such charges are not paid.

Miscellaneous

The depositary will forward to the holders of depositary receipts all reports and communications from us which are delivered to the depositary and which we are required to furnish to the holders of the preferred stock. In addition, the depositary will make available for inspection by holders of depositary receipts at the principal office of the depositary, and at such other places as it may from time to time deem advisable, any reports and communications received from us which are received by the depositary as the holder of preferred stock or equity stock.

Neither the depositary nor we assume any obligation or will be subject to any liability under the deposit agreement to holders of depositary receipts other than for its negligence or willful misconduct. Neither the depositary nor we will be liable if the depositary is prevented or delayed by law or any circumstance beyond its control in performing its obligations under the deposit agreement. Our obligations and those of the depositary under the deposit agreement will be limited to performance in good faith of their duties thereunder, and they will not be obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred stock unless satisfactory indemnity is furnished. We and the depositary may rely on written advice of counsel or accountants, on information provided by holders of depositary receipts or other persons believed in good faith to be competent to give such information and on documents believed to be genuine and to have been signed or presented by the proper party or parties.

Resignation and Removal of Depositary

The depositary may resign at any time by delivering to us notice of its election to do so, and we may at any time remove the depositary, any such resignation or removal to take effect upon the appointment of a successor depositary and its acceptance of such appointment. Such successor depositary must be appointed within 60 days after delivery of the notice for resignation or removal and must be a bank or trust company having its principal office in the United States of America and having a combined capital and surplus of at least $150,000,000.

Federal Income Tax Considerations

Owners of the depositary shares will be treated for federal income tax purposes as if they were owners of the preferred stock or equity stock represented by such depositary shares. Accordingly, such owners will be entitled to take into account, for federal income tax purposes, income and deductions to which they would be entitled if they were holders of such preferred stock. In addition, (i) no gain or loss will be recognized for federal income tax purposes upon the withdrawal of preferred stock in exchange for depositary shares, (ii) the tax basis of each share of preferred stock or equity stock to an exchanging owner of depositary shares will, upon such exchange, be the same as the aggregate tax basis of the depositary shares exchanged therefor, and (iii) the holding period for preferred stock or equity stock in the hands of an exchanging owner of depositary shares will include the period during which such person owned such depositary shares.

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DESCRIPTION OF WARRANTS

We have no warrants outstanding (other than options issued under our stock option plan). We may issue warrants for the purchase of common stock, preferred stock or equity stock. Warrants may be issued independently or together with any other securities offered by any prospectus supplement and may be attached to or separate from such securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between the Company, a warrant agent specified in the applicable prospectus supplement and us. The warrant agent will act solely as our agent in connection with the warrants of such series and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants. The following sets forth certain general terms and provisions of the warrants offered hereby. Further terms of the warrants and the applicable warrant agreement will be set forth in the applicable prospectus supplement.

The applicable prospectus supplement will describe the terms of the warrants in respect of which this prospectus is being delivered, including, where applicable, the following: (1) the title of such warrants; (2) the aggregate number of such warrants; (3) the price or prices at which such warrants will be issued; (4) the designation, number and terms of the shares of common stock, preferred stock or equity stock purchasable upon exercise of such warrants; (5) the designation and terms of the other securities, if any, with which such warrants are issued and the number of such warrants issued with each such security; (6) the date, if any, on and after which such warrants and the related common stock, preferred stock or equity stock, if any, will be separately transferable; (7) the price at which each share of common stock, preferred stock or equity stock purchasable upon exercise of such warrants may be purchased; (8) the date on which the right to exercise such warrants shall commence and the date on which such right shall expire; (9) the minimum or maximum amount of such warrants which may be exercised at any one time; and
(10) any other terms of such warrants, including terms, procedures and limitations relating to the exchange and exercise of such warrants.

CERTAIN FEDERAL INCOME TAX CONSIDERATIONS

The following discussion summarizes certain federal income tax considerations relating to the Company and to the acquisition, ownership and disposition of Common Stock. The applicable Prospectus Supplement will contain information about additional federal income tax considerations, if any, relating to Securities other than Common Stock. The following discussion, which is not exhaustive of all possible tax considerations, does not give a detailed description of any state, local, or foreign tax considerations. Nor does it discuss all of the aspects of federal income taxation that may be relevant to a prospective Shareholder in light of his or her particular circumstances or to certain types of Shareholders (including insurance companies, tax-exempt entities, financial institutions or broker-dealers, foreign corporations and persons who are not citizens or residents of the United States) who are subject to special treatment under federal income tax laws. The information in this section is based on the Code, current, temporary and proposed Treasury Regulations thereunder, the legislative history of the Code, current administrative interpretations and practices of the IRS (including its practices and policies as endorsed in private letter rulings, which are not binding on the IRS except with respect to the taxpayer that receives such a ruling), and court decisions, all as of the date hereof. No assurance can be given that future legislation, Treasury Regulations, administrative interpretations and court decisions will not significantly change current law or adversely affect existing interpretations of current law. Any such change could apply retroactively to transactions preceding the date of the change. The Company has not requested and does not plan to request any rulings from the IRS concerning the tax treatment of the Company or the Operating Partnership. Thus, no assurance can be provided that the statements set forth herein (which do not bind the IRS or the courts) will not be challenged by the IRS or will be sustained by a court if so challenged.

EACH PROSPECTIVE INVESTOR IS ADVISED TO CONSULT THE APPLICABLE PROSPECTUS SUPPLEMENT, AS WELL AS HIS OR HER TAX ADVISOR, REGARDING THE TAX CONSEQUENCES TO HIM OR HER OF THE ACQUISITION, OWNERSHIP AND SALE OF THE SECURITIES, INCLUDING THE FEDERAL, STATE, LOCAL, FOREIGN AND OTHER TAX CONSEQUENCES OF SUCH ACQUISITION, OWNERSHIP AND SALE AND OF POTENTIAL CHANGES IN APPLICABLE TAX LAWS.

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As used under this heading, the term "Company" refers solely to PS Business Parks, Inc.

Taxation of the Company

General. The Company has elected to be taxed as a REIT under Sections 856 through 860 of the Code commencing with its taxable year ended December 31, 1990. The Company believes that its has been organized and operated in a manner so as to qualify as a REIT, and the Company intends to continue to operate in such a manner. So long as the Company qualifies for taxation as a REIT, it generally will not be subject to federal corporate income taxes on net income that it distributes currently to Shareholders. However, the Company will be subject to federal income tax in the following circumstances. First, the Company will be taxed at regular corporate rates on any undistributed REIT taxable income, including undistributed net capital gains. Second, under certain circumstances, the Company may be subject to the "alternative minimum tax" on its items of tax preference. Third, if the Company has (i) net income from the sale or other disposition of "foreclosure property" (which is, in general, property acquired by foreclosure or otherwise on default of a lease or a loan secured by the property) which is held primarily for sale to customers in the ordinary course of business or (ii) other nonqualifying income from foreclosure property, it will be subject to tax at the highest corporate rate on such income. Fourth, if the Company has net income from prohibited transactions (which are, in general, certain sales or other dispositions of property (other than foreclosure property) held primarily for sale to customers in the ordinary course of business), such income will be subject to a 100% tax. Fifth, if the Company should fail to satisfy the 75% gross income test or the 95% gross income test (as discussed below), and has nonetheless maintained its qualification as a REIT because certain other requirements have been met, it will be subject to a 100% tax on the net income attributable to the greater of the amount by which the Company fails the 75% or 95% gross income test. Sixth, if the Company should fail to distribute during each calendar year at least the sum of (i) 85% of its REIT ordinary income for such year, (ii) 95% of its REIT capital gain net income for such year, and (iii) any undistributed taxable income from prior periods, it would be subject to a 4% excise tax on the excess of such required distribution over the amounts actually distributed. Seventh, if the Company acquires or has acquired any asset from a taxable C corporation in a transaction in which the basis of the asset in the acquiror's hands is determined by reference to the basis of the asset (or any other asset) in the hands of the C corporation and the acquiror recognizes gain on the disposition of such asset during the 10 year period beginning on the date on which such asset was acquired by it, then to the extent of such asset's "Built-In Gain" (i.e., the excess of (a) the fair market value of such asset at the time of the acquisition by the Company over (b) the adjusted basis in such asset, determined at the time of such acquisition), such gain will be subject to tax at the highest regular corporate rate applicable, pursuant to anticipated Treasury Regulations that have yet to be promulgated. The results described above with respect to the recognition of Built-In Gain assume that the Company will make an election pursuant to Notice 88-19 with respect to any such acquisition. Prior to 1997, AOPP was taxable as a regular C corporation. In making its election to be taxed as a REIT for 1997, AOPP elected to be subject to the Built-In Gain rules of Notice 88-19.

Requirements for Qualification. The Code defines a REIT as a corporation, trust or association (1) that is managed by one or more trustees or directors,
(2) the beneficial ownership of which is evidenced by transferable shares of stock, or by transferable certificates of beneficial interest, (3) that would be taxable as a domestic corporation, but for Sections 856 through 860 of the Code, (4) that is neither a financial institution nor an insurance company subject to certain provisions of the Code, (5) the beneficial ownership of which is held by 100 or more persons, (6) that during the last half of each taxable year not more than 50% in value of the outstanding stock of which is owned, directly or indirectly, by five or fewer individuals (as defined in the Code to include certain entities), (7) that makes an election to be taxable as a REIT, or has made such election for a previous taxable year which has not been revoked or terminated, and satisfies all relevant filing and other administrative requirements established by the IRS that must be met in order to elect and maintain REIT status; (8) that uses a calendar year for federal income tax purposes and complies with recordkeeping requirements of the Code and regulations promulgated thereunder; and (9) that meets certain other tests, described below, regarding the nature of its income and assets and the amount of its distributions. The Code provides that conditions (1) through
(4), inclusive, must be met during the entire taxable year and that condition
(5) must be

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met during at least 335 days of a taxable year of 12 months, or during a proportionate part of a taxable year of less than 12 months. For purposes of determining stock ownership under condition (6), a supplemental unemployment compensation benefits plan, a private foundation or a portion of a trust permanently set aside or used exclusively for charitable purposes generally is considered an individual. However, a trust that is a qualified trust under Code section 401(a) generally is not considered an individual and beneficiaries of such trust are treated as holding shares of a REIT in proportion to their actuarial interests in such trust for purposes of condition (6).

The Company's Articles of Incorporation contain restrictions regarding the transfer of its capital stock that are intended to assist the Company in continuing to satisfy the stock ownership requirements described in conditions
(5) and (6). See "Description of Common Stock--Ownership Limitations." In connection with condition (6), a REIT is required to send annual letters to its shareholders requesting information regarding the actual ownership of shares. For the Company's taxable years commencing on or after January 1, 1998, if the Company complies with the annual letters requirement and the Company does not know, or exercising reasonable diligence would not have known, whether it failed to meet requirement (6) above, the Company will be treated as having met the requirement.

The ownership restrictions in the Company's articles of incorporation generally prohibit the actual or constructive ownership of more than 2% of the outstanding shares of Common Stock (excluding the interest held by PSI) or more than 9.9% of the outstanding shares of each class or series of shares of Preferred Stock, unless an exception is established by the Board of Directors. The restrictions provide that if, at any time, for any reason, those ownership limitations are violated or more than 50% in value of the Company's outstanding stock otherwise would be considered owned by five or fewer individuals, then a number of shares of stock necessary to cure the violation will automatically and irrevocably be transferred from the person causing the violation to a designated charitable beneficiary.

The REIT protective provisions are modeled after certain arrangements that the IRS has ruled in private letter rulings will preclude a REIT from being considered to violate the ownership restrictions so long as the arrangements are enforceable as a matter of state law and the REIT seeks to enforce them as and when necessary. There can be no assurance, however, that the IRS might not seek to take a different position with respect to the Company (a private letter ruling is legally binding only with respect to the taxpayer to whom it was issued and the Company will not seek a private ruling on this or any other issue) or contend that the Company failed to enforce these various arrangements. Moreover, the Company's limitations will not apply to the ownership of shares at the time of the Merger, or to shares of stock of the Company deemed to be owned by a person as a result of such person's ownership of shares of PSI (however, such deemed ownership will be taken into account in determining whether a subsequent acquisition or transfer of shares of the Company (but not PSI) violates the limitations), exceptions not contained in the private letter rulings previously issued by the IRS. Accordingly, there can be no assurance that these arrangements necessarily will preserve the Company's REIT status. The Company believes, however, that it has issued and outstanding sufficient shares with sufficient diversity of ownership to allow it to satisfy the REIT ownership requirements.

A REIT is not permitted to have at the end of any taxable year any undistributed earnings and profits that are attributable to a "C corporation" taxable year. As a result of the Merger, the Company succeeded to various tax attributes of AOPP, including any undistributed earnings and profits. AOPP was taxable as a "C corporation" prior to 1997, and does not believe that it has transferred any undistributed "C corporation earnings and profits" to the Company. However, neither AOPP nor the Company has sought an opinion of counsel or outside accountants to the effect that the Company has not acquired any "C corporation earnings and profits" from AOPP. There can be no assurance that the IRS would not contend otherwise on a subsequent audit of AOPP. It appears that the Company could keep from being disqualified as a REIT by using "deficiency dividend" procedures to distribute the "C corporation" earnings and profits. In order to use this procedure, an affected REIT would have to make an additional distribution to its shareholders (in addition to distributions made for purposes of satisfying the normal REIT distribution requirements), within 90 days of the IRS determination.

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In addition, the REIT would have to pay to the IRS an interest charge on 50% of the acquired C corporation earnings and profits that were not distributed prior to the end of the REIT's taxable year in which they were acquired. If C corporation earnings and profits were deemed to have been acquired by the Company, there can be no assurance, however, that the IRS would not take the position either that the procedure is not available at all (in which case the Company would fail to qualify as a REIT) or, alternatively, that even if the procedure is available, the Company cannot qualify as a REIT for its taxable year in which the earnings and profits were acquired, but it could qualify as a REIT for subsequent taxable years. Finally, if AOPP were determined not to have qualified as a REIT for the taxable year ended December 31, 1997 or its short taxable year ending at the time of the Merger, the Company would not be eligible to elect REIT status for up to four years after the year in which AOPP failed to qualify as a REIT. AOPP made an election to be taxed as a REIT commencing with its taxable year ended December 31, 1997. The Company and AOPP believe that AOPP's election is valid and that AOPP was organized, and operated in 1997 and until the time of the Merger, in conformity with the requirements for taxation as a REIT.

Income Tests. In order to maintain qualification as a REIT, the Company must satisfy certain gross income requirements, which are applied on an annual basis. First, at least 75% of the Company's gross income (excluding gross income from prohibited transactions) for each taxable year must be derived directly or indirectly from investments relating to real property or mortgages on real property (including "rents from real property" and, in certain circumstances, interest) or from certain types of temporary investments. Second, at least 95% of the Company's gross income (excluding gross income from prohibited transactions) for each taxable year must be derived from the same items which qualify under the 75% income test, and from dividends, interest and gain from the sale or disposition of stock or securities, or from any combination of the foregoing.

Rents received by the Company will qualify as "rents from real property" in satisfying the gross income requirements described above only if several conditions are met. First, the amount of rent must not be based in whole or in part on the income or profits of any person. However, an amount received or accrued generally will not be excluded from the term "rents from real property" solely by reason of being based on a fixed percentage or percentages of receipts or sales. The Company anticipates that none of its annual gross income will be attributable to rents that are based in whole or in part on the income of any person (excluding rents based on a percentage of receipts or sales, which, as described above, are permitted). Second, the Code provides that rents received from a tenant will not qualify as "rents from real property" if the Company, or an owner of 10% or more of the Company, directly or constructively owns 10% or more of such tenant (a "Related Party Tenant"). The Company does not anticipate that it will receive income from Related Party Tenants. Third, if rent attributable to personal property, leased in connection with a lease of real property, is greater than 15% of the total rent received under the lease, then the portion of rent attributable to such personal property will not qualify as "rents from real property." The Company does not anticipate deriving rent attributable to personal property leased in connection with real property that exceeds 15% of the total rents. Finally, for rents to qualify as "rents from real property," the Company generally must not operate or manage the property or furnish or render services to tenants, other than through an "independent contractor" that is adequately compensated and from whom the Company derives no revenue. The "independent contractor" requirement, however, does not apply to the extent the services provided by the Company are "usually or customarily rendered" in connection with the rental of space for occupancy only and are not otherwise considered "rendered to the occupant." Any services with respect to certain properties that the Company believes may not be provided by the Company directly without jeopardizing the qualification of rent as "rents from real property" will be performed by "independent contractors."

For the Company's taxable years commencing on or after January 1, 1998, rents received generally will qualify as rents from real property even if the Company were to provide services that are not permissible services so long as the amount received for such services meets a de minimis standard. The amount received for "impermissible services" with respect to a property (or, if services are available only to certain tenants, possibly with respect to such tenants) cannot exceed 1% of all amounts received, directly or indirectly, by the Company with respect to such property (or, if services are available only to certain tenants, possibly with respect to such tenants). In computing any such amounts, the amount that the Company would be deemed to have received for

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performing "impermissible services" will be the greater of the actual amount so received or 150% of the direct cost to the Company of providing those services. If the impermissible service income exceeds 1% of the Company's total income from a property, then all of the income from that property will fail to qualify as rents from real property.

If the Company fails to satisfy one or both of the 75% or 95% gross income tests for any taxable year, it may nevertheless qualify as a REIT for such year if it is entitled to relief under certain provisions of the Code. It is not possible, however, to state whether in all circumstances the Company would be entitled to the benefit of these relief provisions. Even if these relief provisions were to apply, however, a 100% tax would be imposed with respect to the "excess net income" attributable to the failure to satisfy the 75% and 95% gross income tests.

Asset Tests. The Company, at the close of each quarter of its taxable year, must satisfy three tests relating to the nature of its assets. First, at least 75% of the value of the Company's total assets must be represented by real estate assets. The Company's real estate assets include, for this purpose, its allocable share of real estate assets held by the Operating Partnership and the non-corporate subsidiaries of the Operating Partnership, as well as stock or debt instruments held for less than one year purchased with the proceeds of a stock offering, or long-term (at least five years) debt offering of the Company, cash, cash items and government securities. Second, not more than 25% of the Company's total assets may be represented by securities other than those in the 75% asset class. Third, of the investments included in the 25% asset class, the value of any one issuer's securities owned by the Company may not exceed 5% of the value of the Company's total assets, and, except for REITs or "qualified REIT subsidiaries," the Company may not own more than 10% of any one issuer's outstanding voting securities.

After initially meeting the asset tests at the close of any quarter, the Company will not lose its status as a REIT for failure to satisfy the 25% or 5% asset tests at the end of a later quarter solely by reason of changes in the relative values of its assets. If the failure to satisfy the 25% or 5% asset tests results from an acquisition of securities or other property during a quarter, including, for example, as a result of the Company increasing its interest in the Operating Partnership as a result of a merger, the exercise of unit redemption rights or an additional capital contribution of proceeds of an offering of shares by the Company, the failure can be cured by disposition of sufficient nonqualifying assets within 30 days after the close of that quarter. The Company intends to maintain adequate records of the value of its assets to ensure compliance with the asset tests and to take any available actions within 30 days after the close of any quarter as may be required to cure any noncompliance with the 25% or 5% asset tests. If the Company fails to cure noncompliance with the asset tests within such time period, the Company would cease to qualify as a REIT.

Annual Distribution Requirements. The Company, in order to qualify as a REIT, is required to distribute dividends (other than capital gain dividends) to its shareholders in an amount at least equal to (i) the sum of (a) 95% of the Company's "REIT taxable income" (computed without regard to the dividends paid deduction and the Company's net capital gain) and (b) 95% of the net income (after tax), if any, from foreclosure property, minus (ii) the sum of certain items of non-cash income. In addition, if the Company disposes of any Built-In Gain Asset during the 10 year period beginning on the date the Company acquired that asset, the Company will be required, pursuant to Treasury Regulations which have not yet been promulgated, to distribute at least 95% of the Built-In Gain (after tax), if any, recognized on the disposition of such asset. See "--General" above for a discussion of "Built-In Gain Assets." Such distributions must be paid in the taxable year to which they relate, or in the following taxable year if declared before the Company timely files its tax return for such year and if paid on or before the first regular dividend payment date after such declaration.

To the extent that the Company does not distribute all of its net capital gain or distributes at least 95%, but less than 100%, of its "REIT taxable income," as adjusted, it will be subject to tax thereon at regular ordinary and capital gain corporate tax rates. The Company may elect to require the shareholders to include the Company's undistributed net capital gains in their income by designating, in a written notice to shareholders, those amounts as undistributed capital gains in respect of its shareholders' shares. If the Company makes such

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an election, the shareholders will (i) include in their income as capital gains their proportionate share of such undistributed capital gains and (ii) be deemed to have paid their proportionate share of the tax paid by the Company on such undistributed capital gains and thereby receive a credit or refund for such amount. A shareholder will increase the basis in its Common Shares by the difference between the amount of capital gain included in its income and the amount of the tax that the Company is deemed to have paid on the shareholder's behalf. The earnings and profits of the Company will be adjusted appropriately. For a more detailed description of the tax consequences to a shareholder of such a designation, see "--Taxation of U.S. Shareholders Holding Common Stock."

In addition, if the Company should fail to distribute during each calendar year at least the sum of (i) 85% of its REIT ordinary income for such year,
(ii) 95% of its REIT capital gain income for such year, and (iii) any undistributed taxable income from prior periods, the Company would be subject to a 4% excise tax on the excess of such required distribution over the sum of amounts actually distributed during the calendar year by the REIT and the amount, if any, on which the REIT paid income tax for such year.

The Company intends to make timely distributions sufficient to satisfy its annual distribution requirements. It is expected that the Company's REIT taxable income will be less than its cash flow due to the allowance of depreciation and other non-cash charges in computing REIT taxable income. Accordingly, the Company anticipates that it will generally have sufficient cash or liquid assets to enable it to satisfy the distribution requirements described above. It is possible, however, that the Company, from time to time, may not have sufficient cash or other liquid assets to meet these distribution requirements due to timing differences between (i) the actual receipt of income and actual payment of deductible expenses and (ii) the inclusion of such income and deduction of such expenses in arriving at taxable income of the Company, or due to the need to make nondeductible payments, such as principal payments on any indebtedness it may have. If such circumstances occur, in order to meet the distribution requirements, the Company may find it necessary to arrange for short-term, or possibly long-term, borrowings or to pay dividends in the form of taxable stock dividends.

Under certain circumstances, the Company may be able to rectify a failure to meet the distribution requirement for a year by paying "deficiency dividends" to shareholders in a later year, which may be included in the Company's deduction for dividends paid for the earlier year. Thus, the Company may be able to avoid being taxed on amounts distributed as deficiency dividends; however, the Company will be required to pay interest based upon the amount of any deduction taken for deficiency dividends.

Recordkeeping Requirements. Pursuant to applicable Treasury Regulations, the Company must comply with certain recordkeeping requirements to qualify for taxation as a REIT.

Failure of the Company to Qualify as a REIT. For any taxable year that the Company fails to qualify as a REIT, the Company would be taxed at the usual corporate rates on all of its taxable income. Those taxes would reduce the amount of cash available to the Company for distribution to its Shareholders. Distributions to shareholders in any year in which the Company fails to qualify as a REIT will not be deductible and will not be required to be made. In addition, if the Company fails to qualify as a REIT, all distributions to shareholders will be taxed as ordinary income, to the extent of the Company's current and accumulated earnings and profits, and, subject to certain limitations of the Code, corporate distributees may be eligible for the dividends received deduction.

Unless certain relief provisions apply, the Company's election to be treated as a REIT will terminate automatically if the Company fails to meet the qualification requirements described above and the Company will not be eligible to elect REIT status again until the fifth taxable year that begins after the first year for which the Company's election was terminated (or revoked). If the Company loses its REIT status, but later qualifies and elects to be taxed as a REIT again, the Company may face significant adverse tax consequences.

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Taxation of U.S. Shareholders Holding Common Stock

As used herein, the term "U.S. Shareholder" means a holder of shares of Common Stock who (for United States federal income tax purposes) (i) is a citizen or resident of the United States, (ii) is a corporation, partnership, or other entity created or organized in or under the laws of the United States or any political subdivision thereof, (iii) is an estate the income of which is subject to United States federal income taxation regardless of its source or (iv) is a trust the administration of which is subject to the primary supervision of a United States court and which has one or more Untied States persons who have the authority to control all substantial decisions of the trust. Notwithstanding the preceding sentence, to the extent provided in regulations, certain trusts in existence on August 20, 1996, and treated as United States persons prior to such date that elect to continue to be treated as United States persons, shall also be considered U.S. Shareholders.

Distributions by the Company. As long as the Company qualifies as a REIT, distributions made to the Company's taxable U.S. Shareholders (and not designated as capital gain dividends) will generally be taxable to such Shareholders as ordinary income to the extent of the Company's current or accumulated earnings and profits. For purposes of determining whether distributions on shares of Common Stock are out of current or accumulated earnings and profits, the earnings and profits of the Company will be allocated first to shares of Preferred Stock and second to shares of Common Stock. There can be no assurance that the Company will have sufficient earnings and profits to cover distributions on any shares of Preferred Stock. Such distributions will not be eligible for the dividends received deductions in the case of Shareholders that are corporations. Dividends declared during the last quarter of a calendar year and actually paid during January of the immediately following calendar year generally are treated as if received by the Shareholders on December 31 of the calendar year during which they were declared.

Distributions designated by the Company as capital gain dividends generally will be taxed as gain from the sale or exchange of a capital asset held for more than one year (to the extent that the distributions do not exceed the Company's actual net capital gain for the taxable year) without regard to the period for which the Shareholder has held its stock. Corporate Shareholders however, may be required to treat up to 20% of certain capital gain dividends as ordinary income.

Shareholders may not include in their individual income tax returns any net operating losses or capital losses of the Company. Instead, such losses would be carried over by the Company for potential offset against future income (subject to certain limitations). Distributions made by the Company and gain arising from the sale or exchange by a holder of Common Stock will not be treated as passive activity income, and, as a result, holders of Common Stock generally will not be able to apply any "passive losses" against such income or gain. Future regulations may require that Shareholders take into account, for purposes of computing their individual alternative minimum tax liability, certain tax preference items of the Company. In addition, taxable distributions from the Company generally will be treated as investment income for purposes of the investment interest limitations. Capital gain dividends and capital gain from the disposition of shares, including distributions treated as such, however, will be treated as investment income for purposes of the investment interest limitation only if the U.S. Shareholder so elects, in which case such capital gains will be taxed at ordinary income rates. The Company will notify shareholders after the close of the Company's taxable year as to the portions of distributions attributable to that year that constitute ordinary income, return of capital and capital gain.

Distributions in excess of current or accumulated earnings and profits will not be taxable to a U.S. shareholder to the extent that they do not exceed the adjusted basis of the shareholder's shares of Common Stock, but rather will reduce the adjusted basis of such shares of Common Stock. To the extent that such distributions exceed the adjusted basis of a U.S. shareholder's shares of Common Stock, they will be included in income as capital gains, assuming the shares of Common Stock are a capital asset in the hands of the U.S. Shareholder.

For the Company's taxable years commencing on or after January 1, 1998, the Company may elect to require the holders of Common Stock to include the Company's undistributed net long-term capital gains in their income. If the Company makes such an election, the holders of Common Stock will (i) include in their income as long-term capital gains their proportionate share of such undistributed capital gains and (ii) be deemed to have

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paid their proportionate share of the tax paid by the Company on such undistributed capital gains and thereby receive a credit or refund for such amount. A holder of Common Stock will increase the basis in its Common Stock by the difference between the amount of capital gain included in its income and the amount of the tax it is deemed to have paid. The earnings and profits of the Company will be adjusted appropriately. With respect to such long-term capital gain of a taxable domestic shareholder that is an individual or an estate or trust, the IRS has authority to issue regulations that could apply the special tax rate applicable to sales of depreciable real property by an individual or an estate or trust to the portion of the long-term capital gains of an individual or an estate or trust attributable to deductions for depreciation taken with respect to depreciable real property.

Sales of Shares. In general, a U.S. Shareholder will realize gain or loss on the disposition of shares of Common Stock equal to the difference between (i) the amount of cash and the fair market value of any property received on such disposition and (ii) the shareholder's adjusted basis of such shares of Common Stock. Such gain or loss will be capital gain or loss if the shares have been held as a capital asset. In the case of a taxable U.S. Shareholder who is an individual or an estate or trust, such gain or loss will be long-term capital gain or loss, and such long-term capital gain shall be subject to the maximum capital gain rate of 20%. In the case of a taxable U.S. Shareholder that is a corporation, such gain or loss will be long-term capital gain or loss if such shares have been held for more than one year and any such capital gain shall be subject to the maximum capital gain rate of 35%. Loss upon a sale or exchange of shares of Common Stock by a shareholder who has held such shares of Common Stock for six months or less (after applying certain holding period rules) will be treated as a long-term capital loss to the extent of distributions from the Company required to be treated by such shareholder as long-term capital gain.

Taxpayer Relief Act and IRS Restructuring Act Changes to Capital Gain Taxation. The Taxpayer Relief Act of 1997 (the "Taxpayer Relief Act") altered the taxation of capital gain income. Under the Taxpayer Relief Act, individuals, trusts and estates that hold certain investments for more than 18 months may be taxed at a maximum long-term capital gain rate of 20% on the sale or exchange of those investments. Individuals, trusts and estates that hold certain assets for more than one year but not more than 18 months may be taxed at a maximum long-term capital gain rate of 28% on the sale or exchange of those investments. The Taxpayer Relief Act also provides a maximum rate of 25% for "unrecaptured Section 1250 gain" for individuals, trusts and estates, special rules for "qualified 5-year gain" and other changes to prior law. The recently enacted IRS Restructuring Act of 1998, however, reduced the holding period requirement established by the Taxpayer Relief Act for the application of the 20% and 25% capital gain tax rates to 12 months from 18 months for sales of capital gain assets after December 31, 1997 and thus eliminated the 28% rate. The Taxpayer Relief Act allows the IRS to prescribe regulations on how the Taxpayer Relief Act's capital gain rates will apply to sales of capital assets by "pass-through entities," including REITs, such as the Company and to sales of interests in "pass-through entities." Shareholders are urged to consult with their own tax advisors with respect to the rules contained in the Taxpayer Relief Act and the IRS Restructuring Act.

On November 10, 1997, the IRS issued IRS Notice 97-64, which provides generally that the Company may classify portions of its designated capital- gain dividend as (i) a 20% rate gain distribution (which would be taxed as long-term capital gain in the 20% group), (ii) an unrecaptured Section 1250 gain distribution (which would be taxed as long-term capital gain in the 25% group), or (iii) a 28% rate gain distribution (which would be taxed as long- term capital gain in the 28% group). (If no designation is made, the entire designated capital gain dividend will be treated as a 28% rate gain distribution.) IRS Notice 97-64 provides that a REIT must determine the maximum amounts that it may designate as 20% and 25% rate capital gain dividends by performing the computation required by the Code as if the REIT were an individual whose ordinary income were subject to a marginal tax rate of at least 28%. The Notice further provides that designations made by the REIT will only be effective to the extent that they comply with Revenue Ruling 89-81, which requires that distributions made to different classes of shares be composed proportionately of dividends of a particular type. Although Notice 97-64 will apply to sales of capital gain assets after July 28, 1997 and before January 1, 1998, it is expected that the IRS will issue clarifying guidance, most likely applying the same principles set forth in Notice 97-64, regarding a REIT's designation of capital gain dividends in light of the new holding period requirements.

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Backup Withholding. The Company will report to its domestic shareholders and the IRS the amount of dividends paid during each calendar year, and the amount of tax withheld, if any, with respect thereto. Under the backup withholding rules, a shareholder may be subject to backup withholding at the rate of 31% with respect to dividends paid unless such holder (a) is a corporation or comes within certain other exempt categories and, when required, demonstrates this fact, or (b) provides a taxpayer identification number and certifies as to no loss of exemption from backup withholding. Amounts withheld as backup withholding will be creditable against the stockholder's income tax liability. In addition, the Company may be required to withhold a portion of capital gain distributions made to any shareholders who fail to certify their non-foreign status to the Company. See "--Taxation of Non-U.S. Shareholders" below.

Taxation of Tax-Exempt Shareholders. As a general rule, amounts distributed to a tax-exempt entity by a corporation do not constitute "unrelated business taxable income" ("UBTI"), and thus distributions by the Company to a stockholder that is a tax-exempt entity generally should not constitute UBTI, provided that the tax-exempt entity has not financed the acquisition of its shares of Common Stock with "acquisition indebtedness" within the meaning of the Code and the shares of Common Stock are not otherwise used in an unrelated trade or business of the tax-exempt entity. However, distributions by a REIT to a tax-exempt employee's pension trust that owns more than 10% of the REIT will be treated as UBTI in an amount equal to the percentage of gross income of the REIT that is derived from an "unrelated trade or business" (determined as if the REIT were a pension trust) divided by the gross income of the REIT for the year in which the dividends are paid. This rule only applies, however, if (i) the percentage of gross income of the REIT that is derived from an unrelated trade or business for the year in which the dividends are paid is at least 5%, (ii) the REIT qualifies as a REIT only because the pension trust is not treated as a single individual for purposes of the "five-or-fewer rule" (see "--Taxation of the Company--Requirements for Qualification" above), and
(iii) (A) one pension trust owns more than 25 percent of the value of the REIT or, (B) a group of pension trusts individually holding more than 10 percent of the value of the REIT collectively own more than 50 percent of the value of the REIT. The Company currently does not expect that this rule will apply.

Taxation of Non-U.S. Shareholders

The rules governing U.S. federal income taxation of non-U.S. Shareholders are complex, and the following discussion is intended only as a summary of such rules. Prospective non-U.S. Shareholders should consult with their tax advisors to determine the impact of federal, state, local and foreign income tax laws on an investment in the Company, including any reporting requirements.

Distributions by the Company. Distributions to a non-U.S. Shareholder that are not attributable to gain from sales or exchanges by the Company of U.S. real property interests and not designated by the Company as capital gain dividends will generally be subject to tax as ordinary income to the extent of the Company's current or accumulated earnings and profits as determined for U.S. federal income tax purposes. Such distributions will generally be subject to a withholding tax equal to 30% of the gross amount of the distribution, unless reduced by an applicable tax treaty or unless such dividends are treated as effectively connected with a United States trade or business. If the amount distributed exceeds a non-U.S. Shareholder's allocable share of such earnings and profits, the excess will be treated as a tax-free return of capital to the extent of such non-U.S. Shareholder's adjusted basis in the Common Stock. To the extent that such distributions exceed the adjusted basis of a non-U.S. Shareholder's Common Stock, such distributions will generally be subject to tax if such non-U.S. Shareholder would otherwise be subject to tax on any gain from the sale or disposition of its Common Stock, as described below.

For withholding tax purposes, the Company currently is required to treat all distributions as if made out of its current or accumulated earnings and profits and thus intends to withhold at the rate of 30% (or a reduced treaty rate if applicable) on the amount of any distribution (other than distributions designated as capital gain dividends) made to a Non-U.S. Shareholder. Under regulations generally effective for distributions on or after January 1, 1999, the Company would not be required to withhold at the 30% rate on distributions it reasonably

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estimates to be in excess of the Company's current and accumulated earnings and profits. If it cannot be determined at the time a distribution is made whether such distribution will be in excess of current and accumulated earnings and profits, the distribution will be subject to withholding at the rate applicable to ordinary dividends. As a result of a legislative change made by the Small Business Job Protection Act of 1996, under current law, it appears that the Company will be required to withhold 10% of any distribution to a non-U.S. Shareholder in excess of the Company's current and accumulated earnings and profits. Consequently, although the Company intends to withhold at a rate of 30% on the entire amount of any distribution to a non-U.S. Shareholder (or lower applicable treaty rate), to the extent the Company does not do so, any portion of such a distribution not subject to withholding at a rate of 30% (or lower applicable treaty rate) will be subject to withholding at a rate of 10%. However, the non-U.S. Shareholder may seek a refund of such amounts from the IRS if it subsequently determined that such distribution was, in fact, in excess of current or accumulated earnings and profits of the Company, and the amount withheld exceeded the non-U.S. Shareholder's United States tax liability, if any, with respect to the distribution.

Distributions to a non-U.S. Shareholder that are designated by the Company at the time of distribution as capital gains dividends (other than those arising from the disposition of a United States real property interest) generally will not be subject to United States federal income taxation, unless
(i) the investment in the Common Stock is effectively connected with the non- U.S. Shareholder's United States trade or business, in which case the non-U.S. Shareholder will be subject to the same treatment as U.S. Shareholders with respect to such gain (except that a shareholder that is a foreign corporation may also be subject to the 30% branch profits tax) or (ii) the non-U.S. Shareholder is a nonresident alien individual who is present in the United States for 183 days or more during the taxable year and certain other requirements are met, in which case the nonresident alien individual will be subject to a 30% tax on the individual's capital gains.

Under the Foreign Investment in Real Property Tax Act ("FIRPTA"), distributions to a non-U.S. Shareholder that are attributable to gain from sales or exchanges by the Company of United States real property interests (whether or not designated as a capital gain dividend) will be taxed to a non- U.S. Shareholder at the normal capital gains rates applicable to domestic Shareholders (subject to a special alternative minimum tax in the case of nonresident alien individuals). Also, distributions subject to FIRPTA may be subject to a 30% branch profits tax in the hands of a non-U.S. Shareholder that is a corporation and that is not entitled to treaty relief or exemption. The Company is required by applicable FIRPTA Treasury Regulations to withhold 35% of any such distribution that is or could be designated by the Company as a capital gain dividend. That amount is creditable against the non-U.S. Shareholder's United States FIRPTA tax liability.

Even if the Company does not qualify or ceases to be a domestically controlled REIT, gain arising from the sale or exchange by a non-U.S. Shareholder of Common Stock would still not be subject to U.S. taxation under FIRPTA as a sale of a United States real property interest if (i) the class or series of shares being sold is "regularly traded," as defined by applicable Treasury Regulations, on an established securities market such as the New York Stock Exchange, and (ii) the selling non-U.S. Shareholder owned 5% or less of the value of the outstanding class or series of shares being sold throughout the five-year period ending on the date of the sale or exchange.

If gain on the sale or exchange of Common Stock were subject to taxation under FIRPTA, the non-U.S. Shareholder would be subject to regular United States income tax with respect to such gain in the same manner as a taxable U.S. Shareholder, subject to any applicable alternative minimum tax, a special alternative minimum tax in the case of nonresident alien individuals and the possible application of the 30% branch profits tax in the case of foreign corporations. The purchaser of the Common Stock would be required to withhold and remit to the IRS 10% of the purchase price.

Although the law is not entirely clear on the matter, it appears that amounts designated by the Company pursuant to the Taxpayer Relief Act as undistributed capital gains in respect of shares of Common Stock (see "Taxation of U.S. Shareholders Holding Common Stock" above) would be treated with respect to non-U.S. Shareholders in the manner outlined in the preceding paragraph for actual distributions by the Company of

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capital gain dividends. Under that approach, the non-U.S. Shareholders would be able to offset as a credit against their United States federal income tax liability resulting therefrom their proportionate share of the tax paid by the Company on such undistributed capital gains (and to receive from the IRS a refund to the extent their proportionate share of such tax paid by the Company were to exceed their actual United States federal income tax liability).

Sale of Common Stock. Gain recognized by a non-U.S. Shareholder upon a sale of its Common Stock will generally not be subject to tax under FIRPTA if the Company is a "domestically controlled REIT," which is defined generally as a REIT in which at all times during a specified testing period less than 50% in value of its shares were held directly or indirectly by non-U.S. persons. Because only a minority of the Shareholders are non-U.S. Shareholders, the Company expects to qualify as a "domestically controlled REIT." Accordingly, a non-U.S. Shareholder should not be subject to U.S. tax on gains recognized upon disposition of the Common Stock, provided that such gain is not effectively connected with the conduct of a United States trade or business and, in the case of an individual Shareholder, such holder is not present in the United States for 183 days or more during the year of sale and certain other requirements are met.

Backup Withholding Tax and Information Reporting. Backup withholding tax (which generally is a withholding tax imposed at a rate of 31% on certain payments to persons that fail to furnish certain information under the United States information reporting requirements) and information reporting will generally not apply to distributions paid to non-U.S. Shareholders outside the United States that are treated as (i) dividends subject to the 30% (or lower treaty rate) withholding tax discussed above, (ii) capital gains dividends, or
(iii) distributions attributable to gain from the sale or exchange by the Company of United States real property interests. As a general matter, backup withholding and information reporting will not apply to a payment of the proceeds of a sale of Common Stock by or through a foreign office of a foreign broker. Information reporting (but not backup withholding) will apply, however, to a payment of the proceeds of a sale of Common Stock by a foreign office of a broker that (a) is a United States person, (b) derives 50% or more of its gross income for certain periods from the conduct of a trade or business in the United States or (c) is a "controlled foreign corporation" (generally a foreign corporation controlled by United States Shareholders) for United States tax purposes, unless the broker has documentary evidence in its records that the holder is a non-U.S. Shareholder and certain other conditions are met, or the Shareholder otherwise establishes an exemption. Payment to or through a United States office of a broker of the proceeds of a sale of Common Stock is subject to both backup withholding and information reporting unless the Shareholder certifies under penalty of perjury that the Shareholder is a non-U.S. Shareholder, or otherwise establishes an exemption. A non-U.S. Shareholder may obtain a refund of any amounts withheld under the backup withholding rules by filing the appropriate claim for refund with the IRS.

The United States Treasury Department has recently finalized regulations regarding the withholding and information reporting rules discussed above. In general, these regulations do not alter the substantive withholding and information reporting requirements but unify certification procedures and forms and clarify and modify reliance standards. These regulations generally are effective for payments made after December 31, 1999, subject to certain transition rules. Valid withholding certificates that are held on December 31, 1999, will remain valid until the earlier of December 31, 2000, or the date of the expiration of the certificate under rules currently in effect, unless otherwise invalidated due to changes in the circumstances of the person whose name is on such certificate. A non-U.S. Shareholder should consult its advisor regarding the effect of the new Treasury Regulations.

Administration's Proposed Changes to REIT Qualification Requirements

The administration's fiscal year 2000 budget proposal, announced February 1, 1999, includes a proposal that would change the 10% voting securities test to a 10% vote or value test. Under the proposal, a REIT would not be able to own more than 10% of the vote or value of the outstanding securities of any corporation, except for a qualified REIT subsidiary or another REIT (see "Taxation of the Company--Asset Tests" above). The proposal also contains an exception to the 5% and 10% asset tests that would allow a REIT to have "taxable

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REIT subsidiaries," including both "qualified independent contractor subsidiaries," which could perform noncustomary and other currently prohibited services for tenants and other customers, and "qualified business subsidiaries," which could undertake third-party management and development activities as well as other non-real estate related activities. Under the proposal, no more than 15% of a REIT's total assets could consist of taxable REIT subsidiaries and no more than 5% of a REIT's total assets could consist of qualified independent contractor subsidiaries. Under the budget proposal, a taxable REIT subsidiary would not entitled to deduct any interest on debt funded directly or indirectly by the REIT. This proposal would be effective after the date of enactment and a REIT would be allowed to combine and convert existing corporate subsidiaries into taxable REIT subsidiaries tax-free prior to a certain date. A transition period would allow for conversion of existing corporate subsidiaries before the 10% vote or value test would become effective. For the Company's taxable years after the effective date of the proposal and after any applicable transition period, the 10% vote or value test would apply to the Company's ownership in any of the non-qualified REIT subsidiaries not converted into taxable REIT subsidiaries. It is presently uncertain whether any proposal regarding REIT subsidiaries, including the budget proposal, will be enacted or, if enacted, what the terms, including the effective date, of such proposal will be.

On April 28, 1999, the Real Estate Investment Trust Modernization Act of 1999 (the "bill") was introduced in Congress. The bill is similar to the administration's proposal in several respects. Like the administration's proposal, the bill would create "taxable REIT subsidiaries" that would not be subject to the 5% asset test, but that would remain subject to the 25% asset test (see "Taxation of the Company--Asset Tests" above). The "taxable REIT subsidiaries" would also be subject to "earnings stripping" limitations on the deductibility of interest. Under the bill, a REIT would be able to rent up to 10% of a property to a taxable REIT subsidiary and generally have the rent qualify as good income. The bill would also change the 10% voting securities test to a 10% vote or value test unless the corporation elects to be a taxable REIT subsidiary or the securities qualify for the "grandfather rule." In general, the "grandfather rule" would apply to securities of a corporation in which the REIT owned an interest on April 28, 1999. The grandfather rule would also apply to securities acquired in a tax-free exchange for "grandfathered securities" and to securities acquired in a qualifying tax-free reorganization with another REIT, if those securities were grandfathered in the hands of the other REIT. Securities of a corporation will lose their "grandfathered" status if the corporation acquires any substantial asset or engages in a substantial new line of business after April 28, 1999 (other than pursuant to a binding contract in effect on that date).

Tax Aspects of the Company's Ownership of Interests in the Operating Partnership

General. A significant portion of the Company's investments will be held indirectly through the Operating Partnership. In general, partnerships are "pass-through" entities that are not subject to federal income tax. Rather, partners are allocated their proportionate shares of the items of income, gain, loss, deduction and credit of a partnership, and are potentially subject to tax on those items, without regard to whether the partners receive a distribution from the partnership. In the case of a REIT which is a partner in a partnership, Treasury Regulations provide that for purposes of applying the REIT gross income and gross asset tests, the REIT will be deemed to own its proportionate share of the assets of the partnership and will be deemed to be entitled to the income of the partnership attributable to that share, in each case based on its "capital interest" in the partnership. In addition, the character of the gross income and assets of the partnership shall retain the same character in the hands of the REIT for purposes of Section 856 of the Code which includes the gross income and asset tests described above. The Company will have direct control of the Operating Partnership and intends to operate it consistent with the requirements for qualification as a REIT. The Company will include in its income its proportionate share of the foregoing partnership items for purposes of the various REIT income tests and will take into account its distributive share of partnership items in the computation of its REIT taxable income. Moreover, for purposes of the REIT asset tests, the Company will include its proportionate share of assets held through the Operating Partnership.

Entity Classification. If the Operating Partnership were treated as an association, the entity would be taxable as a corporation and therefore would be subject to an entity level tax on its income. In such a situation,

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the character of the Company's assets and items of gross income would change and would preclude the Company from qualifying as a REIT. The same result could occur if any subsidiary partnership failed to qualify for treatment as a partnership.

Prior to January 1, 1997, an organization formed as a partnership or a limited liability company was treated as a partnership for federal income tax purposes rather than as a corporation only if it had no more than two of the four corporate characteristics that the Treasury Regulations in effect at that time used to distinguish a partnership from a corporation for tax purposes. These four characteristics were (i) continuity of life, (ii) centralization of management, (iii) limited liability and (iv) free transferability of interests.

Under final Treasury Regulations that became effective January 1, 1997, the four factor test has been eliminated and an entity formed as a partnership or as a limited liability company will be taxed as a partnership for federal income tax purposes unless it specifically elects otherwise. The Treasury Regulations provide that the IRS will not challenge the classification of an existing partnership or limited liability company for tax periods prior to January 1, 1997 so long as (1) the entity had a reasonable basis for its claimed classification, (2) the entity and all its members recognized the federal income tax consequences of any changes in the entity's classification within the 60 months prior to January 1, 1997, and (3) neither the entity nor any member of the entity had been notified in writing on or before May 8, 1996, that the classification of the entity was under examination by the IRS.

The Company believes that the Operating Partnership will be treated as a partnership for federal income tax purposes (and not as an association taxable as a corporation).

Partnership Allocations. Although a partnership agreement will generally determine the allocation of income and loss among partners, those allocations will be disregarded for tax purposes if they do not comply with the provisions of Section 704(b) of the Code and the related Treasury Regulations. Generally, those provisions require that partnership allocations reflect the economic arrangement of the partners. The allocations of taxable income and loss provided for in the Operating Partnership Agreement are intended to comply with the requirements of Section 704(b) of the Code and the related Treasury Regulations. If an allocation is not recognized for federal income tax purposes, the item subject to the allocation will be reallocated in accordance with the partners' interests in the partnership, which will be determined by taking into account all of the facts and circumstances relating to the economic arrangement of the partners with respect to that item.

Tax Allocations with Respect to the Properties. Pursuant to Section 704(c) of the Code, income, gain, loss and deduction attributable to appreciated or depreciated property that is contributed to a partnership in exchange for an interest in the partnership, must be allocated in a manner so that the contributing partner is charged with, or benefits from, respectively, the unrealized gain or unrealized loss associated with the property at the time of the contribution. The amount of the unrealized gain or unrealized loss is generally equal to the difference between the fair market value of contributed property at the time of contribution and the adjusted tax basis of the property at that time (a "Book-Tax Difference"). These allocations are solely for federal income tax purposes and do not affect the book capital accounts or other economic or legal arrangements among the partners. Similar rules can apply in the case of appreciated or depreciated properties held by a partnership at the time of new contributions to the partnership. The Operating Partnership was formed by way of contributions of appreciated and depreciated properties. Consequently, the Operating Partnership Agreement requires that those allocations be made in a manner consistent with Section 704(c) of the Code.

In general, the partners of the Operating Partnership who contributed assets will be allocated differing depreciation deductions than if they had retained the contributed property. In addition, on the disposition of any contributed asset that has a Book-Tax Difference, the income or loss attributable to the Book-Tax Difference generally will be allocated to the contributing partner. These allocations will tend to eliminate the Book-Tax Difference over the life of the Operating Partnership. However, the special allocation rules of Section 704(c) do not always entirely eliminate the Book-Tax Difference on an annual basis or with respect to a specific taxable transaction such as a sale. Thus, the carryover basis of the contributed assets in the hands of the Operating

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Partnership may cause the Company to be allocated lower depreciation and other deductions, and possibly an amount of taxable income in the event of a sale of the contributed assets in excess of the economic or book income allocated to it as a result of that sale. Such an allocation might cause the Company to recognize taxable income in excess of cash proceeds, which might adversely affect the Company's ability to comply with the REIT distribution requirements.

Treasury Regulations under Section 704(c) of the Code provide partnerships with a choice of several methods of accounting for Book-Tax Differences, including the "traditional method" or the election of certain methods that would permit any distortions caused by a Book-Tax Difference to be entirely rectified on an annual basis or with respect to a specific taxable transaction such as a sale. The Operating Partnership and the Company will determine with respect to each contribution to the Operating Partnership which method to use.

Taxation of Holders of Preferred Stock, Equity Stock, Depositary Shares and Warrants

If the Company offers one or more series of Preferred Stock, Equity Stock, Depositary Shares or Warrants, there may be tax consequences for the holders of such Securities not discussed herein. For a discussion of any such additional consequences, see the applicable Prospectus Supplement.

State and Local Taxes

The tax treatment of the Company and the Shareholders in states having taxing jurisdiction over them may differ from the federal income tax treatment. Accordingly, no discussion of state taxation of the Company and the Shareholders is provided nor is any representation made as to the tax status of the Company in such states. All investors should consult their tax advisors as to the treatment of the Company under the respective state tax laws applicable to them.

PLAN OF DISTRIBUTION

We may sell the securities to one or more underwriters for public offering and sale by them or may sell the securities to investors directly or through agents. Any such underwriter or agent involved in the offer and sale of the securities will be named in the applicable prospectus supplement.

Direct sales to investors may be accomplished through subscription offerings or through shareholder purchase rights distributed to shareholders. In connection with subscription offerings or the distribution of shareholder purchase rights to shareholders, if all of the underlying securities are not subscribed for, we may sell such unsubscribed securities to third parties directly or through underwriters or agents and, in addition, whether or not all of the underlying securities are subscribed for, we may concurrently offer additional securities to third parties directly or through underwriters or agents. Any such underwriter or agent involved in the offer and sale of the securities will be named in the applicable prospectus supplement. If securities are to be sold through shareholder purchase rights, such shareholder purchase rights will be distributed as a dividend to the shareholders for which they will pay no separate consideration. The prospectus supplement with respect to the offer of securities pursuant to shareholder purchase rights will set forth the relevant terms of the shareholder purchase rights, including (i) whether common shares or common share warrants, or both, will be offered pursuant to the shareholder purchase rights and the number of common shares and common share warrants, as applicable, which will be offered pursuant to the shareholder purchase rights, (ii) the period during which and the price at which the shareholder purchase rights will be exercisable, (iii) the number of shareholder purchase rights then outstanding, (iv) any provisions for changes to or adjustments in the exercise price of the shareholder purchase rights and (v) any other material terms of the shareholder purchase rights.

Underwriters may offer and sell the securities at a fixed price or prices, which may be changed, at prices related to the prevailing market prices at the time of sale or at negotiated prices. We also may, from time to time, authorize underwriters acting as our agents to offer and sell the securities upon the terms and conditions as are set forth in the applicable prospectus supplement. In connection with the sale of securities, underwriters may

33

be deemed to have received compensation from us in the form of underwriting discounts or commissions and may also receive commissions from purchasers of securities for whom they may act as agent. Underwriters may sell securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for whom they may act as agent.

Any underwriting compensation paid by us to underwriters or agents in connection with the offering of securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers, will be set forth in the applicable prospectus supplement. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions, under the Securities Act. Underwriters, dealers and agents may be entitled, under agreements entered into with us, to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act.

Securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms ("remarketing firms"), acting as principals for their own accounts or as our agents. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with the securities remarketed thereby. Remarketing firms may be entitled under agreements which may be entered into with us to indemnification by us against certain liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we will authorize dealers acting as our agents to solicit offers by certain institutions to purchase securities at the offering price set forth in such prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in such prospectus supplement. Each contract will be for an amount not less than, and the aggregate principal amount of securities sold pursuant to contracts shall be not less nor more than, the respective amounts stated in the applicable prospectus supplement. Institutions with whom contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions, and other institutions but will in all cases be subject to our approval. Contracts will not be subject to any conditions except (i) the purchase by an institution of the securities covered by its contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which such institution is subject, and (ii) if the securities are being sold to underwriters, we will have sold to such underwriters the total principal amount of the securities less the principal amount thereof covered by contracts. Agents and underwriters will have no responsibility in respect of the delivery or performance of contracts.

Certain of the underwriters, if any, and their affiliates may be customers of, engage in transactions with and perform services for us in the ordinary course of business.

34

This prospectus may also be used in registered resales by the following holders of common stock:

                                                                               Shares of     Percentage of
                         Shares of Common                       Shares of     Common Stock Outstanding Shares
                              Stock         Percentage of      Common Stock   Beneficially  of Common Stock
                           Beneficially   Outstanding Shares Being Registered Owned After  Beneficially Owned
          Name                Owned        of Common Stock      for Resale       Resale       After Resale
          ----           ---------------- ------------------ ---------------- ------------ ------------------
Acquiport Two
 Corporation............    6,110,265            25.8%          6,110,265              0            0%
State Treasurer, State
 of Michigan............    2,131,611             9.0%            888,172(1)   1,243,439          5.3%
Cohen & Steers Capital
 Management, Inc.(2)....    1,176,234             4.9%            888,171(1)     288,063          1.2%
Morgan Stanley Asset
 Management(2)..........      693,493             2.9%            693,493(1)           0            0%
Harvard Private Capital
 Realty, Inc............      874,074             3.7%            592,114(1)     281,960          1.2%
ABKB/LaSalle Securities
 Limited
 Partnership(2).........    2,331,148             9.9%            592,113(1)   1,739,035          7.4%
Fidelity Real Estate
 Investment Portfolio...      348,219             1.5%            348,219(1)           0            0%
Stanford University.....      437,037             1.8%            296,058(1)     140,979           (3)
The Fidelity REIT
 Collective Pool........       66,048              (3)             44,742(1)      21,306           (3)
State Employees'
 Retirement Fund of the
 State of Delaware......       30,911              (3)             20,940(1)       9,971           (3)
J.W. McConnell Family
 Foundation.............        7,821              (3)              5,298(1)       2,523           (3)


(1) Reflects an aggregate of 4,588,885 shares issued to these holders in May 1998 pursuant to a Common Stock Purchase Agreement dated as of January 23, 1998.

(2) All shares of common stock held as agent for and for the benefit of certain of such holder's clients.

(3) Less than 1%.

This prospectus may also be used in registered resales of common stock by the following persons upon exchange of interests in our operating partnership for common stock:

                          Shares of Common     Shares of Common     Shares of Common
                         Stock Beneficially Stock Being Registered Stock Beneficially
          Name              Owned(1)(2)         for Resale(1)      Owned After Resale
          ----           ------------------ ---------------------- ------------------
Galaxy Partnership......       14,384               14,384                  0
Galaxy Associates,
 L.L.C..................       79,464               79,464                  0
Galaxy Associates II,
 L.L.C. ................       13,669               13,669                  0
Faraton Corp............        1,748                1,748                  0


(1) Reflects shares to be issued upon exchange of interests in our operating partnership.

(2) Less than 1% of the outstanding shares of common stock.

We have registered the shares of common stock by the holders in the tables above to provide them with freely tradeable common stock, but the registration of such shares does not necessarily mean that all of such shares will be issued by us or any will be offered or sold by such holders. We will not receive any proceeds from the offering by such holders.

The holders in the tables above may sell the shares of common stock to investors directly or through agents or to one or more underwriters for public offering and sale by them in any of the types of transactions described above. Any such underwriter or agent involved in the offer and sale of such shares will be named in the applicable prospectus supplement.

35

Any profits realized on sales pursuant to this prospectus by the holders in the tables above of such shares may be regarded as underwriting compensation. We will pay all expenses incident to the offering and sale of such shares, other than commissions, discounts and fees of underwriters, broker-dealers or agents. We have agreed to indemnify the holders of such shares against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.

LEGAL OPINIONS

David Goldberg, our vice president and counsel, has delivered an opinion to the effect that the securities offered by this prospectus will be validly issued, fully paid and nonassessable. Hogan & Hartson L.L.P., Washington, D.C., has delivered an opinion as to our status as a REIT. See "Certain Federal Income Tax Considerations." Mr. Goldberg owns 4,256 shares of common stock, and has options to acquire an additional 7,991 shares of common stock.

EXPERTS

Ernst & Young LLP, independent auditors, have audited our consolidated financial statements and schedule included in our Annual Report on Form 10-K for the year ended December 31, 1998, as set forth in their report, which is incorporated by reference in this prospectus supplement and accompanying prospectus and elsewhere in the registration statement. Our financial statements and schedule are incorporated by reference in reliance on Ernst & Young LLP's report, given on their authority as experts in accounting and auditing.

36

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

The estimated expenses, other than underwriting discounts and commissions, in connection with the offerings of the Securities, are as follows:

Registration Fee--Securities and Exchange Commission............... $ 77,704
Transfer Agent and Depositary Fees.................................  125,000
Rating Agency Fees.................................................  100,000
Printing and Engraving Expenses....................................  200,000
Legal Fees and Expenses............................................  100,000
Accounting Fees and Expenses.......................................  100,000
Miscellaneous......................................................   22,296
                                                                    --------
  Total............................................................ $725,000
                                                                    ========

Item 15. Indemnification of Directors and Officers.

The Company's Articles of Incorporation provide that the Company may indemnify the agents of the Company to the maximum extent permitted under California law. See Articles V and VI of the Restated Articles of Incorporation (Exhibit 3.1) and Article VII of the Restated Bylaws (Exhibit 3.2) which are incorporated herein by this reference. The Company has also entered into indemnity agreements with its management and non-management directors and executive officers. The agreements permit the Company to indemnify directors and executive officers to the maximum extent permitted under California law and prohibit the Company from terminating its indemnification obligations as to acts or omissions of any director or executive officer occurring before the termination. The indemnification and limitations on liability permitted by the Articles of Incorporation and the agreements are subject to the limitations set forth by California law. The Company believes the indemnification agreements will assist it in attracting and retaining qualified individuals to serve as directors and executive officers of the Company.

Item 16. Exhibits.

See Exhibit Index contained herein.

Item 17. Undertakings.

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement;

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post- effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high and of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

II-1


(iii) To include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement;

provided, however, that subparagraphs (i) and (ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in the periodic reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) That, for purposes of determining any liability under the Securities Act, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(4) That, for the purpose of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(5) To remove from registration by means of a post-effective amendment any of the Securities being registered which remains unsold at the termination of the offering.

(6) For purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

(7) For the purpose of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

II-2


SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Glendale, State of California, on the 17th day of May, 1999.

PS BUSINESS PARKS, INC.

     /s/ Ronald L. Havner, Jr.
By: _________________________________
         Ronald L. Havner, Jr.,
               President

Each person whose signature appears below hereby authorizes Ronald L. Havner, Jr. and Harvey Lenkin, and each of them, as attorney-in-fact, to sign on his behalf, individually and in each capacity stated below, any amendment, including post-effective amendments to this Registration Statement, and to file the same, with all exhibits thereto, and all documents in connection therewith, with the Securities and Exchange Commission.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

             Signature                         Capacity                 Date
             ---------                         --------                 ----

   /s/ Ronald L. Havner, Jr.         Chairman of the Board, Chief   May 17, 1999
____________________________________  Executive Officer,
       Ronald L. Havner, Jr.          President
                                      and Director
                                      (principal executive
                                      officer)


       /s/ Jack E. Corrigan          Vice President and Chief       May 17, 1999
____________________________________ Financial Officer
           Jack E. Corrigan          (principal financial officer
                                     and principal accounting
                                     officer)


       /s/ Harvey Lenkin             Director                       May 17, 1999
____________________________________
           Harvey Lenkin


       /s/ Vern O. Curtis            Director                       May 17, 1999
____________________________________
           Vern O. Curtis

     /s/ Arthur M. Friedman          Director                       May 17, 1999
____________________________________
         Arthur M. Friedman

       /s/ James H. Kropp            Director                       May 17, 1999
____________________________________
           James H. Kropp

      /s/ Alan K. Pribble            Director                       May 17, 1999
____________________________________
          Alan K. Pribble

       /s/ Jack D. Steele            Director                       May 17, 1999
____________________________________
           Jack D. Steele

II-3


EXHIBIT INDEX

Exhibit
  No.                                Description
-------                              -----------
 1.1    Form of Underwriting Agreement.(1)
 3.1    Restated Articles of Incorporation.
 3.2    Restated Bylaws.(2)
 4.1    Form of Certificate of Determination for additional series of Preferred
         Stock.(1)
 4.2    Form of Deposit Agreement.(1)
 4.3    Form of Certificate of Determination for series of Equity Stock.(1)
 4.4    Form of Warrant Agreement.(1)
 5.1    Opinion of David Goldberg as to the legality of the securities being
         registered.
 8.1    Opinion of Hogan & Hartson L.L.P. re tax matters.
12.1    Statement on computation of ratio of earnings to fixed charges.(3)
23.1    Consent of Ernst & Young LLP.
23.2    Consent of David Goldberg (included in Exhibit 5.1).
23.3    Consent of Hogan & Hartson L.L.P. (included in Exhibit 8.1).
24.1    Power of Attorney (included on page II-3).


(1) To be filed by amendment or as an exhibit to a document to be incorporated by reference herein in connection with the offering of Securities.

(2) Filed with the registrant's Current Report on Form 8-K dated March 17, 1998 and incorporated herein by reference.

(3) Filed with the registrant's Form 10-Q for the quarterly period ended March 31, 1999 and incorporated herein by reference.

II-4


EXHIBIT 3.1

RESTATED ARTICLES OF INCORPORATION

OF

PS BUSINESS PARKS, INC.

[As filed in the Office of the Secretary of State of the State of California May 17, 1999]

David Goldberg and Jack E. Corrigan certify that:

1. They are the Vice President and Secretary, respectively, of PS Business Parks, Inc., a California corporation (the "Corporation").

2. The Articles of Incorporation of this Corporation are amended and restated to read in full as follows:

I

The name of this corporation is PS BUSINESS PARKS, INC.

II

The purpose of this corporation is to engage in any lawful act or activity for which a corporation may be organized under the General Corporation Law of California other than the banking business, the trust company business or the practice of a profession permitted to be incorporated by the California Corporations Code.

III

3.01 This corporation is authorized to issue only three classes of shares to be designated respectively "Preferred Stock," "Common Stock" and "Equity Stock" and referred to herein either as Preferred Stock or Preferred shares, Common Stock or Common shares or Equity Stock or Equity shares. The total number of shares which this corporation is authorized to issue is Two Hundred Fifty Million (250,000,000); the number of Preferred shares shall be Fifty Million (50,000,000) of the par value of One Cent ($.01) each, the number of Common shares shall be One Hundred Million (100,000,000) of the par value of One Cent ($.01) each and the number of Equity shares shall be One Hundred Million (100,000,000) of the par value of One Cent ($.01) each.

3.02 The Preferred shares may be issued from time to time in one or more series. The Board of Directors is authorized to fix the number of shares of any series of Preferred shares and to determine the designation of any such series. The Board of Directors is also authorized to determine or alter the rights granted to or imposed upon any wholly unissued series of Preferred shares including the dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions), the redemption price or prices and the liquidation preference, and, within the limits and restrictions stated in any resolution or resolutions of the Board of Directors originally fixing the number of shares constituting any series, to increase or decrease (but not below the number of shares then outstanding) the number of shares of any such series subsequent to the issue of shares of that series. In case the number of shares of any series shall be so decreased, the shares constituting such decrease shall resume the status which they had prior to the adoption of the resolution originally fixing the number of shares of such series.


3.03 (a) Subject to any preference with respect to the Preferred shares or the Equity shares, the Common shares shall be entitled to distributions out of funds legally available therefor, when, as and if declared by the Board of Directors.

(b) In the event of any liquidation, dissolution or winding up of this corporation, whether voluntary or involuntary, subject to any preference with respect to the Preferred shares or the Equity shares, the entire assets of this corporation available for distribution to shareholders shall be distributed ratably among the Common shares.

3.04 The Equity shares may be issued from time to time in one or more series. The Board of Directors is authorized to fix the number of shares of any series of Equity shares and to determine the designation of any such series. The Board of Directors is also authorized to determine or alter the rights granted to or imposed upon any wholly unissued series of Equity shares including the dividend rights, dividend rate, conversion rights, voting rights, rights and terms of redemption (including sinking fund provisions), the redemption price or prices and the liquidation rights, and, within the limits and restrictions stated in any resolution or resolutions of the Board of Directors originally fixing the number of shares constituting any series, to increase or decrease (but not below the number of shares then outstanding) the number of shares of any such series subsequent to the issue of shares of that series. In case the number of shares of any series shall be so decreased, the shares constituting such decrease shall resume the status which they had prior to the adoption of the resolution originally fixing the number of shares of such series. The dividend and liquidation rights of the Equity shares shall be junior to the Preferred shares and may be senior to, junior to, or pari passu with, the Common shares.

3.05 There is a series of Preferred shares of this Corporation designated "9 1/4% Cumulative Preferred Stock, Series A" which shall consist of 2,300 shares and shall have the following rights, preferences and privileges:

(a) Dividend Rights.

(1) Dividends shall be payable in cash on the shares of this Series when, as and if declared by the Board of Directors, out of funds legally available therefor: (i) for the period (for the purpose of this Section 3.05, the "Initial Dividend Period") from the Deemed Original Issue Date (as defined below) to but excluding July 1, 1999, and (ii) for each quarterly dividend period thereafter (for the purpose of this Section 3.05, the Initial Dividend Period and each quarterly dividend period being hereinafter individually referred to as a "Dividend Period" and collectively referred to as "Dividend Periods"), which quarterly Dividend Periods shall be in four equal amounts and shall commence on January 1, April 1, July 1 and October 1 in each year (for the purpose of this Section 3.05, each, a "Dividend Period Commencement Date"), commencing on July 1, 1999, and shall end on and include the day next preceding the next Dividend Period Commencement Date, at a rate per annum equal to 9 1/4% of the $25,000 per share stated value thereof (for the purpose of this Section 3.05, the "Dividend Rate"). Dividends on each share of this Series shall be cumulative from the Deemed Original Issue Date of such share and shall be payable, without interest thereon, when, as and if declared by the Board of Directors, on or before March 31, June 30, September 30 and December 31 of each year, commencing on June 30, 1999 or, in the case of shares of this Series with a Deemed Original Issue Date after June 30, 1999, the first such dividend payment da te following such Deemed Original Issue Date; provided, that if any such day shall be a Saturday, Sunday, or a day on which banking institutions in the State of New York or the State of California are authorized or obligated by law to close, or a day which is or is declared a national or a New York or California state holiday (for the purpose of this Section 3.05, any of the foregoing a "Non-

2

Business Day"), then the payment date shall be the next succeeding day which is not a Non-Business Day. Each such dividend shall be paid to the holders of record of shares of this Series as they appear on the stock register of the Corporation on such record date, not more than 45 days nor less than 15 days preceding the payment date thereof, as shall be fixed by the Board of Directors. Dividends on account of arrears for any past Dividend Periods may be declared and paid at any time, without reference to any regular dividend payment date, to holders of record on such date, not more than 45 days nor less than 15 days preceding the payment date thereof, as may be fixed by the Board of Directors. After full cumulative dividends on this Series have been paid or declared and funds therefor set aside for payment, including for the then current Dividend Period, the holders of shares of this Series will not be entitled to any further dividends with respect to that Dividend Period.

"Deemed Original Issue Date" means, for the purpose of this Section 3.05,
(a) in the case of any share which is part of the first issuance of shares of this Series or part of a subsequent issuance of shares of this Series prior to July 1, 1999, the date of such first issuance or subsequent issuance, as the case may be, and (b) in the case of any share which is part of a subsequent issuance of shares of this Series on or after July 1, 1999, the later of (x) July 1, 1999 and (y) the latest Dividend Period Commencement Date which precedes the date of issuance of such share and which succeeds the last Dividend Period for which full cumulative dividends have been paid; provided that, in the case of any share which is part of a subsequent issuance, the date of issuance of which falls between (i) the record date for dividends payable on the first succeeding dividend payment date and (ii) such dividend payment date, the "Deemed Original Issue Date" means, for the purpose of this Section 3.05, the date of the Dividend Period Commencement Date that immediately follows the date of issuance.

(2) Dividends payable on shares of this Series for any period greater or less than a full Dividend Period, including the Initial Dividend Period, shall be computed on the basis of a 360-day year consisting of twelve 30-day months.

(3) The Corporation shall not declare or pay or set apart for payment any dividends on any series of preferred shares ranking, as to dividends, on a parity with or junior to the shares of this Series unless full cumulative dividends have been or contemporaneously are declared and paid, or declared and a sum sufficient for payment thereof is set apart for payment, for all Dividend Periods terminating on or prior to the date of payment of any such dividends on such other series of preferred shares. When dividends are not paid in full upon the shares of this Series and any other series of preferred shares ranking on a parity therewith as to dividends, all dividends declared upon shares of this Series and any other series of preferred shares ranking on a parity therewith as to dividends shall be declared pro rata so that the amount of dividends declared per share on the shares of this Series and such other series of preferred shares shall in all cases bear to each other that same ratio that the accumulated dividends per share on the shares of this Series and such other series of preferred shares bear to each other. Except as provided in the preceding sentence, unless full cumulative dividends on the shares of this Series have been paid for all past Dividend Periods, no dividends (other than in shares of the Corporation's common stock, par value $.01 per share (together with any other shares of capital stock of the Corporation into which such shares shall be reclassified or changed (for the purpose of this Section 3.05, "Common Shares"), or another stock ranking junior to the shares of this Series as to dividends and upon liquidation) shall be declared or paid or set aside for payment nor shall any other distribution be made upon the Common Shares or on any other stock of the Corporation ranking junior to or on a parity with the shares of this Series as to dividends or upon liquidation. Unless full cumulative dividends on the shares of this Series have been paid for all past Dividend Periods, no Common Shares or any other stock of the Corporation ranking junior to or on a parity with the shares of this Series as to dividends or upon liquidation shall be redeemed, purchased, or

3

otherwise acquired for any consideration (or any moneys be paid to or made available for a sinking fund for the redemption of any shares of any such stock) by the Corporation or any subsidiary, except by conversion into or exchange for stock of the Corporation ranking junior to the shares of this Series as to dividends and upon liquidation.

(b) Liquidation.

In the event of any voluntary or involuntary liquidation, dissolution, or winding up of the Corporation, the holders of shares of this Series are entitled to receive out of the assets of the Corporation available for distribution to shareholders, before any distribution of assets is made to holders of Common Shares or any other class or series of shares ranking junior to the shares of this Series upon liquidation, liquidating distributions in the amount of $25,000 per share plus all accumulated and unpaid dividends (whether or not earned or declared) for the then current and all past Dividend Periods. If, upon any voluntary or involuntary liquidation, dissolution, or winding up of the Corporation the amounts payable with respect to the shares of this Series and any other shares of the Corporation ranking as to any such distribution on a parity with the shares of this Series are not paid in full, the holders of shares of this Series and of such other shares will share ratably in any such distribution of assets of the Corporation in proportion to the full respective preferential amounts to which they are entitled. After payment of the full amount of the liquidating distribution to which they are entitled, the holders of shares of this Series will not be entitled to any further participation in any distribution of assets by the Corporation.

(1) Written notice of any such liquidation, dissolution or winding up of the Corporation, stating the payment date or dates when, and the place or places where the amounts distributable in such circumstances shall be payable, shall be given by first class mail, postage pre-paid, not less than 30 nor more than 60 days prior to the payment date stated therein, to each record holder of the shares of this Series at the respective addresses of such holders as the same shall appear on the stock transfer records of the Corporation.

(2) For purposes of liquidation rights, a reorganization (as defined in Section 181 of the California Corporations Code) or consolidation or merger of the Corporation with or into any other corporation or corporations or a sale of all or substantially all of the assets of the Corporation shall be deemed not to be a liquidation, dissolution or winding up of the Corporation.

(c) Redemption.

(1) Except as provided in clause (9) below, the shares of this Series are not redeemable prior to April 30, 2004. On and after such date, the shares of this Series are redeemable at the option of the Corporation, by resolution of the Board of Directors, in whole or in part, from time to time upon not less than 30 nor more than 60 days' notice, at a cash redemption price of $25,000 per share plus all accumulated and unpaid dividends (whether or not earned or declared) to the date of redemption.

(2) If fewer than all the outstanding shares of this Series are to be redeemed, the number of shares to be redeemed will be determined by the Board of Directors, and such shares shall be redeemed pro rata from the holders of record of such shares in proportion to the number of such shares held by such holders (with adjustments to avoid redemption of fractional shares) or by lot in a manner determined by the Board of Directors.

4

(3) Notwithstanding the foregoing, if any dividends, including any accumulation, on the shares of this Series are in arrears, no shares of this Series shall be redeemed unless all outstanding shares of this Series are simultaneously redeemed, and the Corporation shall not purchase or otherwise acquire, directly or indirectly, any shares of this Series; provided, however, that the foregoing shall not prevent the purchase or acquisition of shares of this Series pursuant to a purchase or exchange offer provided such offer is made on the same terms to all holders of shares of this Series.

(4) Immediately prior to any redemption of shares of this Series, the Corporation shall pay, in cash, any accumulated and unpaid dividends through the redemption date, unless a redemption date falls after a dividend payment record date and prior to the corresponding dividend payment date, in which case each holder of shares of this Series at the close of business on such dividend payment record date shall be entitled to the dividend payable on such shares on the corresponding dividend payment date notwithstanding the redemption of such shares before such dividend payment date. Except as expressly provided herein above, the Corporation shall make no payment or allowance for unpaid dividends, whether or not in arrears, on shares of this Series called for redemption.

(5) Notice of redemption shall be given by publication in a newspaper of general circulation in the County of Los Angeles and The City of New York, such publication to be made once a week for two successive weeks, commencing not less than 30 nor more than 60 days prior to the date fixed for redemption thereof. A similar notice will be mailed by the Corporation by first class mail, postage pre-paid, to each record holder of the shares of this Series to be redeemed, not less than 30 nor more than 60 days prior to such redemption date, to the respective addresses of such holders as the same shall appear on the stock transfer records of the Corporation. Each notice shall state: (i) the redemption date; (ii) the number of shares of this Series to be redeemed; (iii) the redemption price; (iv) the place or places where certificates for such shares are to be surrendered for payment of the redemption price; and (v) that dividends on the shares to be redeemed will cease to accumulate on such redemption date. If fewer than all the shares of this Series held by any holder are to be redeemed, the notice mailed to such holder shall also specify the number of shares of this Series to be redeemed from such holder.

(6) In order to facilitate the redemption of shares of this Series, the Board of Directors may fix a record date for the determination of the shares to be redeemed, such record date to be not less than 30 nor more than 60 days prior to the date fixed for such redemption.

(7) Notice having been given as provided above, from and after the date fixed for the redemption of shares of this Series by the Corporation (unless the Corporation shall fail to make available the money necessary to effect such redemption), the holders of shares selected for redemption shall cease to be shareholders with respect to such shares and shall have no interest in or claim against the Corporation by virtue thereof and shall have no voting or other rights with respect to such shares, except the right to receive the moneys payable upon such redemption from the Corporation, less any required tax withholding amount, without interest thereon, upon surrender (and endorsement or assignment of transfer, if required by the Corporation and so stated in the notice) of their certificates, and the shares represented thereby shall no longer be deemed to be outstanding. If fewer than all the shares represented by a certificate are redeemed, a new certificate shall be issued, without cost to the holder thereof, representing the unredeemed shares. The Corporation may, at its option, at any time after a notice of redemption has been given, deposit the redemption price for the shares of this Series designated for redemption and not yet redeemed, plus any accumulated and unpaid dividends thereon to the date fixed for redemption, with the transfer agent or agents for this Series, as a trust fund for the benefit of the holders of the shares of this Series designated for redemption, together with irrevocable instructions and authority to such transfer

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agent or agents that such funds be delivered upon redemption of such shares and to pay, on and after the date fixed for redemption or prior thereto, the redemption price of the shares to their respective holders upon the surrender of their share certificates. From and after the making of such deposit, the holders of the shares designated for redemption shall cease to be shareholders with respect to such shares and shall have no interest in or claim against the Corporation by virtue thereof and shall have no voting or other rights with respect to such shares, except the right to receive from such trust fund the moneys payable upon such redemption, without interest thereon, upon surrender (and endorsement, if required by the Corporation) of their certificates, and the shares represented thereby shall no longer be deemed to be outstanding. Any balance of such moneys remaining unclaimed at the end of the five-year period commencing on the date fixed for redemption shall be repaid to the Corporation upon its request expressed in a resolution of its Board of Directors.

(8) Any shares of this Series that shall at any time have been redeemed shall, after such redemption, have the status of authorized but unissued preferred shares, without designation as to series until such shares are once more designated as part of a particular series by the Board of Directors.

(9) If the Board of Directors of the Corporation shall, at any time and in good faith, be of the opinion that ownership of securities of the Corporation has or may become concentrated to an extent that may prevent the Corporation from qualifying as a real estate investment trust under the REIT Provisions of the Internal Revenue Code (as defined below), then the Board of Directors shall have the power, by lot or other means deemed equitable by them to prevent the transfer of and/or to call for redemption a number of shares of this Series sufficient, in the opinion of the Board of Directors, to maintain or bring the direct or indirect ownership thereof into conformity with the requirements of such a real estate investment trust under the REIT Provisions of the Internal Revenue Code. The redemption price to be paid for shares of this Series so called for redemption, on the date fixed for redemption, shall be the closing price of the shares on the principal national stock exchange on which the shares are listed on the last business day prior to the redemption date, or if no sales of shares were made on such date, the average of the highest bid and the lowest asked quotations on the last business day prior to the redemption date as reported by the National Quotation Bureau, Incorporated or a similar organization selected from time to time by the Corporation or if there be no such bid and asked quotations, as determined by the Board of Directors in good faith; provided that if interests in shares of this Series are represented by depositary shares, then the redemption price shall be determined in accordance with the foregoing, but with respect to one depositary share, multiplied by the number of depositary shares that together represent an interest in one share of this Series. From and after the date fixed for redemption by the Board of Directors, the holder of any shares of this Series so called for redemption shall cease to be entitled to any distributions, voting rights and other benefits with respect to such shares of this Series, other than the right to payment of the redemption price determined as aforesaid. "REIT Provisions of the Internal Revenue Code" shall mean, for the purpose of this Section 3.05, Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. In order to exercise the redemption option set forth in this clause (9), with respect to the shares of this Series, the Corporation shall give notice of redemption by publication in a newspaper of general circulation in the County of Los Angeles and The City of New York, such publication to be made once a week for two successive weeks, commencing not less than 30 nor more than 60 days prior to the date fixed for redemption. A similar notice will be mailed by the Corporation by first class mail, postage pre-paid, to each record holder of the shares of this Series to be redeemed, not less than 30 nor more than 60 days prior to such redemption date, to the respective addresses of such holders as the same shall appear on the stock transfer records of the Corporation. Each notice shall state: (i) the redemption date; (ii) the number of shares of this Series to be redeemed; (iii) the redemption price; (iv) the place or places where certificates for such shares are to be surrendered for payment of the redemption

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price; and (v) that dividends on the shares to be redeemed will cease to accumulate on such redemption date. If fewer than all the shares of this Series held by any holder are to be redeemed, the notice mailed to such holder shall also specify the number of shares of this Series to be redeemed from such holder.

(d) Voting Rights. The shares of this Series shall not have any voting powers either general or special, except as required by law, except that:

(1) If the Corporation shall fail to pay full cumulative dividends on the shares of this Series or any other of its preferred shares for six quarterly dividend payment periods, whether or not consecutive (for the purpose of this
Section 3.05, a "Dividend Default"), the holders of all outstanding preferred shares, voting as a single class without regard to series, will be entitled to elect two Directors until full cumulative dividends for all past dividend payment periods on all preferred shares have been paid or declared and funds therefor set apart for payment. Such right to vote separately as a class to elect Directors shall, when vested, be subject, always, to the same provisions for the vesting of such right to elect Directors separately as a class in the case of future Dividend Defaults. At any time when such right to elect Directors separately as a class shall have so vested, the Corporation may call, and, upon the written request of the holders of record of not less than 20% of the total number of preferred shares of the Corporation then outstanding, shall call, a special meeting of stockholders for the election of Directors. In the case of such a written request, such special meeting shall be held within 90 days after the delivery of such request and, in either case, at the place and upon the notice provided by law and in the Bylaws of the Corporation, provided that the Corporation shall not be required to call such a special meeting if such request is received less than 120 days before the date fixed for the next ensuing Annual Meeting of Shareholders of the Corporation and the holders of all classes of outstanding preferred shares are afforded the opportunity to elect such Directors (or fill any vacancy) at such Annual Meeting of Shareholders. Directors elected as aforesaid shall serve until the next Annual Meeting of Shareholders of the Corporation or until their respective successors shall be elected and qualified. If, prior to the end of the term of any Director elected as aforesaid, a vacancy in the office of such Director shall occur during the continuance of a Dividend Default by reason of death, resignation, or disability, such vacancy shall be filled for the unexpired term by the appointment of a new Director for the unexpired term of such former Director, such appointment to be made by the remaining Director elected as aforesaid.

(2) The affirmative vote or consent of the holders of at least 66 2/3% of the outstanding shares of this Series, voting separately as a class, will be required for any amendment to the Articles of Incorporation of the Corporation that will adversely alter or change the powers, preferences, privileges or rights of the shares of this Series, except as set forth below. The affirmative vote or consent of the holders of at least 66 2/3% of the outstanding shares of this Series and any other series of preferred shares ranking on a parity with this Series as to dividends and upon liquidation, voting as a single class without regard to series, will be required to issue, authorize or increase the authorized amount of any class or series of shares ranking prior to this Series as to dividends or upon liquidation or to issue or authorize any obligation or security convertible into or evidencing a right to purchase any such security, but the Articles of Incorporation may be amended to increase the number of authorized preferred shares ranking on a parity with or junior to this Series or to create another class of preferred shares ranking on a parity with or junior to this Series without the vote of the holders of outstanding shares of this Series.

(3) Nothing herein shall be taken to require a class vote or consent in connection with the authorization, designation, increase or issuance of any shares of any class or series (including additional preferred shares of any series) that rank junior to or on a parity with this Series as to

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dividends and liquidation rights or in connection with the authorization, designation, increase or issuance of any bonds, mortgages, debentures or other debt obligations of the Corporation.

(e) Conversion. The shares of this Series are not convertible into shares of any other class or series of the capital stock of the Corporation.

3.06 There is a series of Preferred shares of this Corporation designated "8 7/8% Series B Cumulative Redeemable Preferred Stock" which shall consist of 510,000 shares and shall have the following rights, preferences and privileges:

1. Rank. The 8 7/8% Series B Cumulative Redeemable Preferred Stock

(for the purpose of this Section 3.06, the "Series B Preferred Stock") will, with respect to distributions and rights upon voluntary or involuntary liquidation, winding-up or dissolution of the Corporation, or both, rank senior to all classes or series of Common Shares and to all classes or series of equity securities of the Corporation now or hereafter authorized, issued or outstanding, other than any class or series of equity securities of the Corporation expressly designated as ranking on a parity with or senior to the Series B Preferred Stock as to distributions and rights upon voluntary or involuntary liquidation, winding-up or dissolution of the Corporation. For purposes of this Section 3.06, the term "Parity Preferred Stock" shall be used to refer to any class or series of capital stock of the Corporation now or hereafter authorized, issued or outstanding expressly designated by the Corporation to rank on a parity with Series B Preferred Stock with respect to distributions and rights upon voluntary or involuntary liquidation, winding-up or dissolution of the Corporation (including the Corporation's 9 1/4% Cumulative Preferred Stock, Series A). For purposes of the preceding sentence, "capital stock" means any equity securities (including Common Shares and Preferred Stock), shares, participation or other ownership interests (however designated) and any rights (other than debt securities convertible into or exchangeable for equity securities) or options to purchase any of the foregoing.

2. Distributions Rights. (a) Payment of Distributions. Subject to the rights of holders of Parity Preferred Stock as to the payment of distributions, holders of Series B Preferred Stock shall be entitled to receive the Series B Priority Return, when, as and if declared by the Board of Directors of the Corporation, out of funds legally available for the payment of distributions. Such distributions shall be cumulative, shall accrue from the original date of issuance of the Series B Preferred Stock and will be payable (A) quarterly in arrears, on March 31, June 30, September 30 and December 31 of each year commencing on the last day of the calendar quarter following the date of issuance of such stock and, (B) in the event of a redemption, on the redemption date (for the purpose of this Section 3.06, each a "Series B Preferred Stock Distribution Payment Date"). If any Preferred Stock Distribution Payment Date is not a Business Day (as defined herein), then payment of the distribution to be made on such date shall be made on the Business Day immediately preceding such Preferred Stock Distribution Payment Date in each case with the same force and effect as if made on such date. Distributions on the Series B Preferred Stock will be made to the holders of record of the Series B Preferred Stock on the relevant record dates to be fixed by the Board of Directors of the Corporation, which record dates shall in no event be more than 45 days or less than 15 days prior to the relevant Series B Preferred Stock Distribution Payment Date (for the purpose of this Section 3.06, each a "Distribution Record Date").

For purposes of this Section 3.06, the following terms shall have the meanings set forth herein: (i) "Liquidation Preference" shall mean, with respect to the Series B Preferred Stock, $25.00 per share of Series B Preferred Stock, plus the amount of any accumulated and unpaid Series B Priority Return (as hereinafter defined) with respect to such share, whether or not declared, minus any distributions in

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excess of the Series B Priority Return that has occurred with respect to such Series B Preferred Stock, to the date of payment; (ii) "Series B Priority Return" shall mean an amount equal to 8 7/8% per annum of the Liquidation Preference per share of Series B Preferred Stock, commencing on the date of issuance of such share of Series B Preferred Stock, determined on the basis of a 365-day year (and actual days for any period), cumulative to the extent not distributed on any Series B Preferred Stock Distribution Payment Date; and (iii) "Business Day" shall mean each day, other than a Saturday or a Sunday, which is not a day on which banking institutions in New York, New York are authorized or required by law, regulation or executive order to close.

(b) Prohibition on Distributions. No distributions on Series B Preferred Stock shall be authorized by the Board of Directors of the Corporation or paid or set apart for payment by the Corporation at any such time as the terms and provisions of any agreement of the Corporation including any agreement relating to indebtedness, prohibits such authorization, payment or setting apart for payment or provides that such authorization, payment or setting apart for payment would constitute a breach thereof or a default thereunder, or to the extent that such authorization or payment shall be restricted or prohibited by law.

(c) Distributions Cumulative. Distributions on the Series B Preferred Stock will accrue whether or not the terms and provisions of any agreement of the Corporation, including any agreement relating to its indebtedness at any time prohibits the current payment of distributions, whether or not the Corporation has earnings, whether or not there are funds legally available for the payment of such distributions and whether or not such distributions are authorized or declared. Accrued but unpaid distributions on the Series B Preferred Stock will accumulate as of the Series B Preferred Stock Distribution Payment Date on which they first become payable. Distributions on account of arrears for any past distribution periods may be declared and paid at any time, without reference to a regular Series B Preferred Stock Distribution Payment Date to holders of record of the Series B Preferred Stock on the record date fixed by the Board of Directors which date shall not be more than 45 days or less than 15 days prior to the payment date. Accumulated and unpaid distributions will not bear interest.

(d) Priority as to Distributions. (i) So long as any Series B Preferred Stock is outstanding, no distribution of cash or other property shall be authorized, declared, paid or set apart for payment on or with respect to any class or series of Common Shares or any class or series of other stock of the Corporation ranking junior as to the payment of distributions or rights upon voluntary or involuntary dissolution, liquidation or winding-up of the Corporation to the Series B Preferred Stock (for the purpose of this Section 3.06, such Common Shares or other junior stock, collectively, "Junior Stock"), nor shall any cash or other property be set aside for or applied to the purchase, redemption or other acquisition for consideration of any Series B Preferred Stock, any Parity Preferred Stock or any Junior Stock, unless, in each case, all distributions accumulated on all Series B Preferred Stock and all classes and series of outstanding Parity Preferred Stock have been paid in full. The foregoing sentence shall not prohibit (i) distributions payable solely in Junior Stock, and (ii) the conversion of Series B Preferred Stock, Junior Stock or Parity Preferred Stock into stock of the Corporation ranking junior to the Series B Preferred Stock as to distributions.

(ii) So long as distributions have not been paid in full (or a sum sufficient for such full payment is not irrevocably deposited in trust for payment) upon the Series B Preferred Stock, all distributions authorized and declared on the Series B Preferred Stock and all classes or series of outstanding Parity Preferred Stock with respect to distributions shall be authorized and declared so that the amount of distributions authorized and declared per share of Series B Preferred Stock and such other

9

classes or series of Parity Preferred Stock shall in all cases bear to each other the same ratio that accrued distributions per share on the Series B Preferred Stock and such other classes or series of Parity Preferred Stock (which shall not include any accumulation in respect of unpaid distributions for prior distribution periods if such class or series of Parity Preferred Stock do not have cumulative distribution rights) bear to each other.

(e) No Further Rights. Holders of Series B Preferred Stock shall not be entitled to any distributions, whether payable in cash, other property or otherwise, in excess of the full cumulative distributions described herein.

3. Liquidation. (a) Payment of Liquidating Distributions. Subject to the rights of holders of Parity Preferred Stock with respect to rights upon any voluntary or involuntary liquidation, dissolution or winding-up of the Corporation and subject to any series of capital stock ranking senior to the Series B Preferred Stock with respect to rights upon any voluntary or involuntary liquidation, dissolution or winding-up of the Corporation, the holders of Series B Preferred Stock shall be entitled to receive out of the assets of the Corporation legally available for distribution or the proceeds thereof, after payment or provision for debts and other liabilities of the Corporation, but before any payment or distributions of the assets shall be made to holders of Common Shares or any other class or series of shares of the Corporation that ranks junior to the Series B Preferred Stock as to rights upon liquidation, dissolution or winding-up of the Corporation, an amount equal to the Liquidation Preference per share of Series B Preferred Stock. If upon such voluntary or involuntary liquidation, dissolution or winding-up, there are insufficient assets to permit full payment of liquidating distributions to the holders of Series B Preferred Stock and any Parity Preferred Stock as to rights upon liquidation, dissolution or winding-up of the Corporation, all payments of liquidating distributions on the Series B Preferred Stock and such Parity Preferred Stock shall be made so that the payments on the Series B Preferred Stock and such Parity Preferred Stock shall in all cases bear to each other the same ratio that the respective rights of the Series B Preferred Stock and such other Parity Preferred Stock (which shall not include any accumulation in respect of unpaid distributions for prior distribution periods if such Parity Preferred Stock does not have cumulative distribution rights) upon liquidation, dissolution or winding-up of the Corporation bear to each other.

(b) Notice. Written notice of any such voluntary or involuntary liquidation, dissolution or winding-up of the Corporation, stating the payment date or dates when, and the place or places where, the amounts distributable in such circumstances shall be payable, shall be given by (i) fax and (ii) by first class mail, postage pre-paid, not less than 10 and not more than 60 days prior to the payment date stated therein, to each record holder of the Series B Preferred Stock at the respective addresses of such holders as the same shall appear on the share transfer records of the Corporation.

(c) No Further Rights. After payment of the full amount of the liquidating distributions to which they are entitled, the holders of Series B Preferred Stock will have no right or claim to any of the remaining assets of the Corporation.

(d) Consolidation, Merger or Certain Other Transactions. The voluntary sale, conveyance, lease, exchange or transfer (for cash, shares of stock, securities or other consideration) of all or substantially all of the property or assets of the Corporation to, or the consolidation or merger or other business combination of the Corporation with or into, any corporation, trust or other entity (or of any corporation, trust or other entity with or into the Corporation) or a statutory share exchange shall not be deemed to constitute a liquidation, dissolution or winding-up of the Corporation.

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4. Redemption. (a) Right of Optional Redemption. The Series B Preferred Stock may not be redeemed prior to April 23, 2004. On or after such date, the Corporation shall have the right to redeem the Series B Preferred Stock, in whole (but not in part), at any time, upon not less than 30 nor more than 60 days' written notice, at a redemption price, payable in cash, equal to the Liquidation Preference (for the purpose of this Section 3.06, the "Series B Redemption Price").

(b) Limitation on Redemption. The redemption price of the Series B Preferred Stock will be payable solely to the extent such payment would be permitted as a distribution under the California Corporations Code.

(c) Procedures for Redemption. (i) Notice of redemption will be (i) faxed, and (ii) mailed by the Corporation, postage prepaid, not less than 30 nor more than 60 days prior to the redemption date, addressed to the respective holders of record of the Series B Preferred Stock to be redeemed at their respective addresses as they appear on the transfer records of the Corporation. No failure to give or defect in such notice shall affect the validity of the proceedings for the redemption of any Series B Preferred Stock except as to the holder to whom such notice was defective or not given. In addition to any information required by law or by the applicable rules of any exchange upon which the Series B Preferred Stock may be listed or admitted to trading, each such notice shall state: (i) the redemption date, (ii) the redemption price,
(iii) the number of shares of Series B Preferred Stock to be redeemed, (iv) the place or places where such shares of Series B Preferred Stock are to be surrendered for payment of the redemption price, (v) that distributions on the Series B Preferred Stock to be redeemed will cease to accumulate on such redemption date and (vi) that payment of the redemption price and any accumulated and unpaid distributions will be made upon presentation and surrender of such Series B Preferred Stock.

(ii) If the Corporation gives a notice of redemption in respect of Series B Preferred Stock (which notice will be irrevocable) then, by 12:00 noon, New York City time, on the redemption date, the Corporation will deposit irrevocably in trust for the benefit of the Series B Preferred Stock being redeemed funds sufficient to pay the applicable Series B Redemption Price, and will give irrevocable instructions and authority to pay such Series B Redemption Price to the holders of the Series B Preferred Stock upon surrender of the certificate evidencing the Series B Preferred Stock by such holders at the place designated in the notice of redemption. On and after the date of redemption, distributions will cease to accumulate on the Series B Preferred Stock called for redemption, unless the Corporation defaults in the payment thereof. If any date fixed for redemption of Series B Preferred Stock is not a Business Day, then payment of the redemption price payable on such date will be made on the next succeeding day that is a Business Day (and without any interest or other payment in respect of any such delay) except that, if such Business Day falls in the next calendar year, such payment will be made on the immediately preceding Business Day, in each case with the same force and effect as if made on such date fixed for redemption. If payment of the Series B Redemption Price or any accumulated or unpaid distributions in respect of the Series B Preferred Stock is improperly withheld or refused and not paid by the Corporation, distributions on such Series B Preferred Stock will continue to accumulate from the original redemption date to the date of payment, in which case the actual payment date will be considered the date fixed for redemption for purposes of calculating the applicable Series B Redemption Price.

(d) Status of Redeemed Stock. Any Series B Preferred Stock that shall at any time have been redeemed shall after such redemption, have the status of authorized but unissued Preferred Stock, without designation as to class or series until such shares are once more designated as part of a particular class or series by the Board of Directors.

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5. Voting Rights. (a) General. Holders of the Series B Preferred Stock will not have any voting rights, except as set forth below.

(b) Right to Elect Directors. If the Corporation shall fail to pay full cumulative dividends on the shares of Series B Preferred Stock or any other of its preferred shares for six quarterly dividend payment periods, whether or not consecutive (for the purpose of this Section 3.06, a "Dividend Default"), the holders of all outstanding preferred shares, voting as a single class without regard to series, will be entitled to elect two Directors until full cumulative dividends for all past dividend payment periods on all preferred shares have been paid or declared and funds therefor set apart for payment. Such right to vote separately as a class to elect Directors shall, when vested, be subject, always, to the same provisions for the vesting of such right to elect Directors separately as a class in the case of future Dividend Defaults. At any time when such right to elect Directors separately as a class shall have so vested, the Corporation may call, and, upon the written request of the holders of record of not less than 20% of the total number of preferred shares of the Corporation then outstanding, shall call, a special meeting of stockholders for the election of Directors. In the case of such a written request, such special meeting shall be held within 90 days after the delivery of such request and, in either case, at the place and upon the notice provided by law and in the Bylaws of the Corporation; provided that the Corporation shall not be required to call such a special meeting if such request is received less than 120 days before the date fixed for the next ensuing Annual Meeting of Shareholders of the Corporation and the holders of all classes of outstanding preferred shares are afforded the opportunity to elect such Directors (or fill any vacancy) at such Annual Meeting of Shareholders. Directors elected as aforesaid shall serve until the next Annual Meeting of Shareholders of the Corporation or until their respective successors shall be elected and qualified. If, prior to the end of the term of any Director elected as aforesaid, a vacancy in the office of such Director shall occur during the continuance of a Dividend Default by reason of death, resignation, or disability, such vacancy shall be filled for the unexpired term by the appointment of a new Director for the unexpired term of such former Director, such appointment to be made by the remaining Director elected as aforesaid.

(c) Certain Voting Rights. So long as any Series B Preferred Stock or Series B Preferred Units exchangeable into Series B Preferred Stock remain outstanding, the Corporation shall not, without the affirmative vote of the holders of a majority of the Series B Preferred Stock outstanding at the time
(i) designate or create, or increase the authorized or issued amount of, any class or series of shares ranking prior to the Series B Preferred Stock with respect to payment of distributions or rights upon liquidation, dissolution or winding-up or reclassify any authorized shares of the Corporation into any such shares, or create, authorize or issue any obligations or security convertible into or evidencing the right to purchase any such shares, (ii) designate or create, or increase the authorized or issued amount of, any Parity Preferred Stock or reclassify any authorized shares of the Corporation into any such shares, or create, authorize or issue any obligations or security convertible into or evidencing the right to purchase any such shares, but only to the extent such Parity Preferred Stock is issued to an Affiliate of the Corporation on terms that differ from the terms of any Parity Preferred Stock issued to the public or non-Affiliates of the Corporation, or (iii) either (A) consolidate, merge into or with, or convey, transfer or lease its assets substantially as an entirety, to any corporation or other entity, or (B) amend, alter or repeal the provisions of the Corporation's Charter (including this Section 3.06) or By- laws, whether by merger, consolidation or otherwise, in each case that would materially and adversely affect the powers, special rights, preferences, privileges or voting power of the Series B Preferred Stock or the holders thereof; provided, however, that with respect to the occurrence of a merger, consolidation or a sale or lease of all of the Corporation's assets as an entirety, so long as (a) the Corporation is the surviving entity and the Series B Preferred Stock remains outstanding with the terms thereof unchanged, or (b) the resulting, surviving or transferee entity is a corporation organized under the laws of any state and substitutes the Series B

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Preferred Stock for other preferred stock having substantially the same terms and same rights as the Series B Preferred Stock, including with respect to distributions, voting rights and rights upon liquidation, dissolution or winding-up, then the occurrence of any such event shall not be deemed materially and adversely affect such rights, privileges or voting powers of the holders of the Series B Preferred Stock; and provided, further, that any increase in the amount of authorized Preferred Stock or the creation or issuance of any other class or series of Preferred Stock, or any increase in an amount of authorized shares of each class or series, in each case ranking either (a) junior to the Series B Preferred Stock with respect to payment of distributions and the distribution of assets upon liquidation, dissolution or winding-up, or (b) on a parity with the Series B Preferred Stock with respect to payment of distributions or the distribution of assets upon liquidation, dissolution or winding-up to the extent such Preferred Stock is not issued to an Affiliate of the Corporation on terms that differ from the terms of any Parity Preferred Stock issued to the public or non-Affiliates of the Corporation, shall not be deemed to materially and adversely affect such rights, preferences, privileges or voting powers.

The affirmative vote or consent of the holders of at least 66 2/3% of the outstanding shares of this Series and any other series of preferred shares ranking on a parity with this Series as to dividends and upon liquidation, voting as a single class without regard to series, will be required to issue, authorize or increase the authorized amount of any class or series of shares ranking prior to this Series as to dividends or upon liquidation or to issue or authorize any obligation or security convertible into or evidencing a right to purchase any such security, but subject to clause 5(c)(ii) of this
Section 3.06, the Articles of Incorporation may be amended to increase the number of authorized preferred shares ranking on a parity with or junior to this Series or to create another class of preferred shares ranking on a parity with or junior to this Series without the vote of the holders of outstanding shares of this Series.

6. Conversion. The holders of the Series B Preferred Stock shall not have any rights to convert such shares into shares of any other class or series of stock or into any other securities of, or interest in, the Corporation.

7. No Sinking Fund. No sinking fund shall be established for the retirement or redemption of Series B Preferred Stock.

8. No Preemptive Rights. No holder of the Series B Preferred Stock of the Corporation shall, as such holder, have any preemptive rights to purchase or subscribe for additional shares of stock of the Corporation or any other security of the Corporation which it may issue or sell.

IV

4.01 Ownership Limitations

(a) Basic Ownership Limits. Except as provided in Section 4.01(b) and
Section 4.03, no Person shall Beneficially Own shares of Common Stock or any series of Preferred Stock or Equity Stock in excess of the Ownership Limit set forth in this Section 4.01(a). In the case of Common Stock, the Ownership Limit is 7.0% of the outstanding shares of Common Stock. In the case of any series of Preferred Stock or Equity Stock, the Ownership Limit is 9.9% of the outstanding shares of such series of Preferred Stock or Equity Stock.

(b) Certain Exceptions. The limitation set forth in Section 4.01(a) shall apply only to a Transfer of Stock or other event with respect to Stock occurring subsequent to the effective date of the

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merger of American Office Park Properties, Inc. with and into this corporation. Notwithstanding anything to the contrary in this Section 4.01, no Person shall be deemed to exceed the Ownership Limit set forth in Section 4.01(a) solely by reason of the Beneficial Ownership of shares of any class of Stock to the extent such shares of Stock were Beneficially Owned by such Person on the effective date of the merger of American Office Park Properties, Inc. with and into this corporation (but the Beneficial Ownership of any such shares of Stock shall be taken into account in determining whether any subsequent Transfer or other event violates Section 4.01(a)). For purposes of the preceding sentence, in evaluating Beneficial Ownership of any Person on the effective date of the merger, there shall also be taken into account Beneficial Ownership of any shares that would have been Beneficially Owned on that date if redemption rights provided in the Operating Partnership Agreement had been exercised at that time (whether or not then exercisable) resulting in an exchange of partnership units for shares. In addition, no Person shall be deemed to exceed the Ownership Limit set forth in
Section 4.01(a) solely by reason of the Beneficial Ownership of shares of any class of Stock that are treated as owned because of such Person's actual or Beneficial Ownership of shares of Public Storage, Inc., to the extent that such Person's actual or Beneficial Ownership of shares of Public Storage, Inc. complies with the ownership restrictions applicable to shareholders of Public Storage, Inc. (but the Beneficial Ownership of any such shares of Stock because of such Person's actual or Beneficial Ownership of shares of Public Storage, Inc. shall be taken into account in determining whether any other Transfer, Acquisition or other event violates Section 4.01(a)).

(c) No Ownership Producing "Closely Held" Status. Notwithstanding any other provisions contained in the corporation's Articles of Incorporation, no Person shall Beneficially Own shares of any class of Stock of this corporation to the extent that, if effective, such Beneficial Ownership would result in this corporation being "closely held" within the meaning of Section 856(h) of the Code (without regard to whether the ownership interest is purportedly held during the second half of a taxable year) or otherwise would result in this corporation failing to qualify as a REIT.

(d) Application to Partnership Exchange Rights. It is expressly intended that the restrictions on ownership and transfer described in this Article IV shall apply to the redemption rights provided in the Operating Partnership Agreement. Notwithstanding any provisions of the Operating Partnership Agreement or any related agreements to the contrary, partners of the Partnership shall not be entitled to exchange interests in the Partnership for Stock to the extent the Beneficial Ownership of those shares would violate the restrictions otherwise contained in this Article IV (taking into account the provisions of Section 4.01(b)).

4.02 Remedies

(a) Transfers in Trust. If, notwithstanding the other provisions contained in this Article IV, at any time after the effective date of the merger of American Office Park Properties, Inc. with and into this corporation, there is a purported Transfer or other event that, if effective, would result in the violation of one or more of the restrictions on ownership and transfer described in Section 4.01, then that number of shares of Stock the Beneficial Ownership of which otherwise would cause such Person to violate Section 4.01 (rounded up to the next whole share) shall be automatically transferred to a Charitable Trust for the benefit of a Charitable Beneficiary, as described in Section 4.08, effective as of the close of business on the day immediately prior to the date of such purported Transfer or other event, and such Person shall acquire no rights in such shares of Stock.

(b) Void Ab Initio. If the transfer to the Charitable Trust described in Section 4.02(a) would not be effective for any reason to prevent any Person from Beneficially Owning Stock in violation

14

of Section 4.01, then the Transfer or other event that would otherwise cause such Person to violate Section 4.01 shall be void ab initio.

(c) No Ownership by Less than 100 Persons. Notwithstanding any other provision of the corporation's Articles of Incorporation, any Transfer of shares of Stock (whether or not such Transfer is the result of a transaction engaged in through the facilities of the Exchange or any other automated inter-dealer quotation system) that, if effective, would result in the Stock being owned beneficially by less than 100 persons (determined under the principles of
Section 856(a)(5) of the Code) shall be void ab initio, and the intended transferee shall acquire no rights in such shares of Stock.

(d) Other Actions. In addition to, and without limitation by, Section 4.02(a) through (c) above, if the Board of Directors or its designees shall at any time determine in good faith that a Transfer or other event has taken place in violation of Article IV or that a Person intends to acquire or has attempted to acquire, ownership, beneficial ownership (determined under the principles of
Section 856(a)(5) of the Code) or Beneficial Ownership of any Stock in violation of Article IV (whether or not the violation is intended), the Board of Directors or its designees shall take such action as it deems advisable to refuse to give effect to or to prevent such Transfer or other event, including, but not limited to, causing this corporation to redeem Stock, refuse to give effect to such Transfer or other event on the books of this corporation or instituting proceedings to enjoin such Transfer or other event; provided, however, that any Transfer or attempted Transfer or other event in violation of Section 4.01 shall automatically result in the transfer to the Charitable Trust described in
Section 4.02(a), without regard to any action (or non-action) by the Board of Directors, and if applicable, such Transfer or other event shall be void ab initio as provided above without regard to any action or inaction by the Board of Directors or its designees.

(e) No Limit on Authority. Nothing contained in this Section 4.02 shall limit the authority of the Board of Directors to take such other action as it deems necessary or advisable to protect this corporation and the interests of its stockholders by preservation of this corporation's status as a REIT.

4.03 Waivers and Exceptions

(a) Board May Grant Exceptions. Subject to Section 4.01(c), the Board of Directors, in its sole and absolute discretion, may grant to any Person an exception to the Ownership Limit set forth in Section 4.01(a) with respect to Common Stock or any series of Preferred Stock or Equity Stock if the Board of Directors shall have determined that this corporation would not be "closely held" within the meaning of Section 856(h) of the Code (without regard to whether the purported Acquisition, Transfer or other event takes place during the second half of a taxable year) and would not otherwise fail to qualify as a REIT, after giving effect to an acquisition by such Person of Beneficial Ownership of the maximum amount of Common Stock, Preferred Stock and Equity Stock permitted as a result of the exception to be granted, and taking into account the existing and permitted ownership by other Persons of the Stock of this corporation (taking into account any other exceptions granted under this
Section 4.03(a)). If a member of the Board of Directors requests that the Board of Directors grant an exception to the Ownership Limit with respect to such member or with respect to any other Person if such member of the Board of Directors would be considered to be the Beneficial Owner of shares of Stock owned by such Person, such member of the Board of Directors shall not participate in the decision of the Board of Directors as to whether to grant any such exception.

(b) Conditions to Exceptions. As a condition to the granting of an exception under Section 4.03(a) to any Person, the Board of Directors may require such Person to provide the Board of

15

Directors such representations and undertakings as the Board of Directors may, in its sole and absolute discretion, require (including, without limitation, an agreement as to a reduced Ownership Limit for such Person with respect to the Beneficial Ownership of one or more other classes of Stock not subject to the exception), and such Person must agree that any violation of such representations and undertakings or attempted violations will result in the application of the remedies set forth in Section 4.02 with respect to shares of Stock producing the violation or attempted violation. In addition, prior to granting any exception, the Board of Directors may require a ruling from the IRS or an opinion of counsel, in either case in form and substance satisfactory to the Board of Directors, in its sole and absolute discretion as it may deem necessary or advisable in order to determine or ensure this corporation's status as a REIT, provided, however, that obtaining a favorable ruling or opinion shall not be required for the Board of Directors to grant an exception.

4.04 Certain Definitions

Unless the context otherwise requires, the terms defined in this
Section 4.04 shall have, for all purposes, the meanings specified below (with terms defined in the singular having comparable meanings when used in the plural).

"Beneficial Ownership" shall mean ownership of Common Stock or Preferred Stock or Equity Stock by a Person, whether the interest in the shares of Stock is held directly or indirectly (including by a nominee), and shall include interests that would be treated as owned through the application of
Section 544 of the Code, as modified by Section 856(h)(1)(B) of the Code. The terms "Beneficial Owner," "Beneficially Owns," and "Beneficially Owned" shall have correlative meanings.

"Charitable Beneficiary" shall mean one or more beneficiaries of the Charitable Trust as determined pursuant to Section 4.08, provided that each such organization must be described in Section 501(c)(3) of the Code and contributions to each such organization must be eligible for deduction under each of Sections 170(b)(1)(A), 2055, and 2522 of the Code.

"Charitable Trust" shall mean the trust created pursuant to Section 4.08(a).

"Charitable Trustee" shall mean the Person that is initially appointed by this corporation, or any successor subsequently designated by this corporation, to serve as trustee of the Charitable Trust provided that such Person is unaffiliated with this corporation or the Purported Owner.

"Code" shall mean the Internal Revenue Code of 1986, as amended from time to time.

"Exchange" shall mean the New York Stock Exchange or the American Stock Exchange.

"IRS" shall mean the United States Internal Revenue Service.

"Market Price" shall mean, with respect to any class or series of Stock, the last reported sales price on the Exchange of such shares on the day immediately preceding the relevant date, or if such shares are not then traded on the Exchange, the last reported sales price of such shares on the day immediately preceding the relevant date as reported on any exchange or quotation system or for which such shares may be traded, provided, however, that if the Board of Directors determines in good faith that a lower price is appropriate, then the Market Price shall be such lower price as determined in good faith by the Board of Directors, or if such shares are not then traded over any exchange or quotation system, the

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Market Price shall be the price determined in good faith by the Board of Directors of this corporation as the fair market value of shares on the relevant date.

"Operating Partnership Agreement" shall mean that certain Agreement of Limited Partnership of American Office Park Properties, L.P. dated January 1, 1997, as amended from time to time.

"Ownership Limit" shall mean the maximum amount of Common Stock and/or Preferred Stock and/or Equity Stock that may be Beneficially Owned by a Person under Section 4.01(a), determined without regard to any exception or waiver that may be granted under Section 4.03 (but taking into account ownership permitted under Section 4.01(b)).

"Person" shall mean an individual, corporation, partnership, limited liability company, estate, trust (including a trust qualified under Section 401(a) or 501(c)(17) of the Code), a portion of a trust permanently set aside for or to be used exclusively for the purposes described in Section 642(c) of the Code, association, private foundation within the meaning of Section 509(a) of the Code, joint stock company or other entity; but does not include, to the extent appropriate to facilitate a public offering or private placement of Stock, an underwriter that participates in such a public offering or private placement provided that the ownership of Stock by such underwriter would not result in this corporation being "closely held" within the meaning of Section 856(h) of the Code and would not otherwise result in this corporation failing to qualify as a REIT.

"Purported Owner" shall mean, with respect to any purported Acquisition that would result in a violation of the limitations in Section 4.01, the Person who would have owned shares of Stock if such Acquisition had been valid under Section 4.01 and, if appropriate in the context, shall also mean any Person who would have been the record owner of the shares that the Purported Owner would have so owned.

"REIT" shall mean a "real estate investment trust" within the meaning of Section 856 of the Code.

"Stock" shall mean shares of stock of this corporation that are Common Stock or Preferred Stock or Equity Stock.

"Transfer" shall mean any issuance, sale, transfer, gift, assignment, devise or other disposition of Stock, as well as any other event that causes a Person to acquire Beneficial Ownership, including (i) the granting or exercise of any option or warrant, convertible security, pledge, security interest, or similar right to acquire Stock or entering into any agreement for the sale, transfer or other disposition of Stock or (ii) the sale, transfer, assignment or other disposition of any securities (or rights convertible into or exchangeable for Stock), (iii) a change in the capital structure of the corporation, (iv) a change in the relationship between two or more Persons that causes a change in ownership of Stock by application of Section 544 of the Code, as modified by
Section 856(h), or (v) Transfers of interests in other entities that result in changes in Beneficial Ownership of Stock; in each case, whether voluntarily or involuntarily, whether owned of record or beneficially or Beneficially, and whether by operation of law or otherwise. (For purposes of this Article 4, the right of a limited partner under the Operating Partnership Agreement to require the partnership to redeem the partner's limited partnership units shall not be considered to be an option or similar right to acquire Stock.)

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4.05 Reporting of Transfers and Ownership

(a) Notice of Restricted Transfers. Any Person who acquires or attempts or intends to acquire Stock or other securities in violation of Article IV or any Person who is a transferee in a Transfer or is otherwise affected by an event other than a Transfer that results in a violation of Article IV, shall immediately give written notice to this corporation of such event, or in the case of such a proposed or attempted event, give at least 15 days prior written notice to this corporation of such event, and shall provide to this corporation such other information as this corporation may request in order to determine the effect, if any, of such acquisition, ownership or other event on this corporation's status as a REIT and to ensure compliance with the limitations set forth in this Article IV.

(b) Owners Required to Provide Information. From and after the effective date of the merger of American Office Park Properties, Inc. with and into this corporation, each Person who is a beneficial owner or Beneficial Owner of Stock and each Person (including the stockholder of record) who is holding Stock for a Beneficial Owner shall provide to this corporation such information as this corporation may request, in good faith, in order to determine this corporation's status as a REIT, to ensure compliance with the limitations set forth in this Article IV, to comply with the requirements of any taxing authority or governmental agency, or to determine any such compliance.

4.06 Ambiguity

In the case of an ambiguity or uncertainty in the interpretation or application of any of the provisions of this Article IV, including any definition contained in Section 4.04, the Board of Directors shall have the power to determine the interpretation or application of the provisions with respect to any situation based on the facts known to it. The value of outstanding shares of any class or series of the Stock of the Corporation may be determined by the Board of Directors in good faith, and any such determination shall be conclusive. If any provision of Article IV requires an action by the Board of Directors but does not provide specific guidance with respect to such action, the Board of Directors shall have the power to determine the action to be taken so long as such action is not contrary to the provisions of Article IV.

4.07 Legend

Each certificate for shares of any class of Stock shall bear substantially the following legend or such other legend as the corporation may from time-to-time determine to be appropriate:

"The shares of Stock represented by this certificate are subject to restrictions on ownership and transfer for the purpose of assisting this corporation to maintain its status as a Real Estate Investment Trust under the Internal Revenue Code of 1986, as amended. Except as set forth in Article IV of this corporation's Articles of Incorporation, no person may Beneficially Own (i) more than 7.0% of the outstanding shares of Common Stock of this corporation, or (ii) more than 9.9% of the outstanding shares of any series of Preferred Stock or Equity Stock of this corporation, with certain further restrictions and exceptions as are set forth in this corporation's Articles of Incorporation. Any Person who attempts to own or Beneficially Own Stock in excess of the above limitations must notify this corporation in writing at least 15 days prior to such attempt. If any of the restrictions on transfer or ownership set forth in Article IV of the Articles of Incorporation are violated, the Stock represented hereby will be automatically transferred to the Charitable Trustee of a Charitable Trust for the benefit of a Charitable Beneficiary pursuant to the terms of

18

Article IV of the Articles of Incorporation. In addition, attempted transfers of Stock in violation of the limitations described above (as modified or expanded upon in Article IV of the Articles of Incorporation), may be void ab initio. All capitalized terms in this legend have the meanings defined in this corporation's Articles of Incorporation, as the same may be amended from time to time. This corporation will furnish to the holder hereof, upon request and without charge, a complete written statement of the terms and conditions of Article IV of the Articles of Incorporation. Requests for such documents may be directed to the corporate secretary."

4.08 Transfer of Stock in Trust

(a) Ownership in Trust; Status of Shares Held in Charitable Trust. Upon any purported Transfer (whether or not such Transfer is the result of a transaction engaged in through the facilities of the Exchange or any other automated inter-dealer quotation system) or other event that results in the transfer of Stock to a Charitable Trust pursuant to Section 4.02, such shares of Stock shall be deemed to have been transferred to the Charitable Trustee in its capacity as Charitable Trustee for the exclusive benefit of one or more Charitable Beneficiaries. Each Charitable Beneficiary shall be designated by this corporation as provided in Section 4.08(f). Shares of Stock so held in Charitable Trust shall remain issued and outstanding shares of Stock of the Corporation and shall be entitled to the same rights and privileges on identical terms and conditions as are all other issued and outstanding shares of Stock of the same class and series.

The Purported Owner shall not benefit economically from ownership of any shares of Stock held in Charitable Trust by the Charitable Trustee, shall have no rights to dividends and shall not possess any rights to vote or other rights attributable to the shares held in Charitable Trust. The Purported Owner of shares of Stock in violation of Section 4.01 shall have no claim, cause of action, or any other recourse whatsoever against the purported transferor of such shares.

(b) Distribution and Dividend Rights. The Charitable Trustee shall have all rights to distributions and dividends with respect to shares of Stock held in the Charitable Trust, which rights shall be exercised for the exclusive benefit of the Charitable Beneficiary. Any distributions or dividend declared but unpaid shall be paid when due to the Charitable Trustee. Any distributions or dividends paid prior to the discovery by this corporation that the shares of Stock have been transferred to the Charitable Trustee with respect to such shares shall be paid over to the Charitable Trustee by the recipient upon demand. The corporation may take all measures that it determines reasonably necessary to recover the amount of any such distribution, including, if necessary, withholding any portion of future distributions payable on shares of Stock of the Purported Owner or amounts otherwise payable to the Purported Owner (such as pursuant to Section 4.08(d)); and, as soon as reasonably practicable following the corporation's receipt or withholding thereof, shall pay over to the Charitable Trustee, the distributions so received or withheld, as the case may be. Any distributions or dividends so paid over to the Charitable Trustee shall be held in trust for the Charitable Beneficiary.

(c) Rights upon Liquidation. In the event of any voluntary or involuntary liquidation, dissolution or winding up of or any distribution of the assets of this corporation, the Charitable Trustee shall be entitled to receive, ratably with each other holder of Stock of the class or series of Stock that is held in the Charitable Trust, that portion of the assets of this corporation available for distribution to the holders of such class or series (determined based upon the ratio that the number of shares of such class or series of Stock held by the Charitable Trustee bears to the total number of shares of such class or series

19

of Stock then outstanding). The Charitable Trustee shall distribute any such assets received in respect of the Stock held in the Charitable Trust in any liquidation, dissolution or winding up of, or distribution of the assets of the Corporation in accordance with Section 4.08(d).

(d) Sale of Shares by Charitable Trustee. As reasonably promptly as possible after receiving notice from this corporation that shares of Stock have been transferred to the Charitable Trust, in an orderly fashion so as not to affect the Market Price of the shares held in the Charitable Trust materially and adversely, the Charitable Trustee shall sell the shares held in Charitable Trust to a Person, designated by the Charitable Trustee, whose ownership of the shares of Stock held in the Charitable Trust would not violate the ownership limitations set forth in Section 4.01. Upon such sale, the interest of the Charitable Beneficiary in the shares sold shall terminate and the Charitable Trustee shall distribute the net proceeds of the sale to the Purported Owner and to the Charitable Beneficiary as provided in this Section 4.08(d).

The Charitable Trustee shall first pay all reasonable expenses of the Charitable Trust and of the corporation incurred in connection with the formation of the Charitable Trust and disposition of the shares. The Purported Owner shall receive out of any excess the lesser of (1) (x) the price per share such Purported Owner paid for the Stock in the purported Transfer that resulted in the transfer of shares of Stock to the Charitable Trust, or (y) if the Transfer or other event that resulted in the transfer of shares of Stock to the Charitable Trust was not a transaction in which the Purported Owner gave full value for such shares of Stock, a price per share equal to the Market Price on the date of the purported Transfer or other event that resulted in the transfer of such shares of Stock to the Charitable Trust and (2) the price per share received by the Charitable Trustee from the sale or other disposition of the shares held in the Charitable Trust. Any net sales proceeds in excess of the amount payable to the Purported Owner shall be immediately paid to the Charitable Beneficiary.

If, prior to the discovery by this corporation that shares of Stock have been transferred to the Charitable Trustee, such shares are sold by the Purported Owner, then (i) such shares shall be deemed to have been sold on behalf of the Charitable Trust and (ii) to the extent that the Purported Owner received an amount for such shares that exceeds the amount such Purported Owner was entitled to receive pursuant to this Section 4.08(d), such excess shall be paid to the Charitable Trustee upon demand.

The Charitable Trustee shall have the right and power (but not the obligation) to offer any share of Stock held in the Charitable Trust for sale to this corporation on such terms and conditions as the Charitable Trustee shall determine appropriate.

Each Charitable Beneficiary and Purported Owner waive any and all claims that they may have against the Charitable Trustee and the corporation arising out of the disposition of shares, except for claims arising out of the gross negligence or willful misconduct of such Charitable Trustee or the corporation, or the Charitable Trustee's or the corporation's failure to make payments in accordance with Section 4.08.

(e) Voting and Notice Rights. The Charitable Trustee shall have all voting rights and rights to receive any notice of any meetings, which rights shall be exercised for the exclusive benefit of the Charitable Beneficiary. The Purported Owner shall have no voting rights with respect to shares held in Charitable Trust. Any vote by or on behalf of a Purported Owner as a holder of shares of Stock prior to the discovery by the corporation that the shares of Stock have been transferred to the Charitable Trust shall be subject to rescission by the Charitable Trustee if the rescission is permitted by applicable law and the Board of Directors concludes that the rescission will not materially and adversely affect the corporation.

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In the case of any such rescission, to the extent permitted by applicable law, any such votes shall be void ab initio with respect to the shares held by the Charitable Trustee.

Notwithstanding the provisions of this Article IV, until the corporation has received notification that shares of Stock have been transferred to the Charitable Trustee, the corporation shall be entitled to rely on its share transfer and other stockholder records for purposes of preparing lists of stockholders entitled to vote at meetings, determining the validity and authority of proxies and otherwise conducting votes of stockholders.

(f) Designation of Charitable Beneficiary(ies). By written notice to the Charitable Trustee, this corporation shall designate one or more nonprofit organizations to be the Charitable Beneficiary of the interest in the Charitable Trust such that (1) the shares of Stock held in the Charitable Trust would not violate the restrictions set forth in Section 4.01 in the hands of such Charitable Beneficiary and (2) each Charitable Beneficiary is described in
Section 501(c)(3) of the Code and contributions to each such organization must be eligible for deduction under each of Sections 170(b)(1)(A), 2055, and 2522 of the Code.

4.09 Settlement

Nothing in this Article IV shall preclude the settlement of any transaction entered into through the facilities of the Exchange (but the fact that settlement of a transaction is permitted shall not negate the effect of any other provision and all of the provisions shall apply to the purported transferee of the shares of Stock in such transaction).

V

The liability of directors of the corporation for monetary damages shall be eliminated to the fullest extent permissible under California law.

VI

The corporation is authorized to provide indemnification of agents (as defined in Section 317 of the California Corporations Code) through bylaw provisions, agreements with agents, vote of shareholders or disinterested directors or otherwise, in excess of the indemnification otherwise permitted by
Section 317 of the California Corporations Code, subject only to the applicable limits set forth in Section 204 of the California Corporations Code with respect to actions for breach of duty to the corporation and its shareholders.

3. The foregoing amendment and restatement has been approved by the Board of Directors of the Corporation.

4. The foregoing amendment has been approved by the required vote of the shareholders of the Corporation in accordance with Section 902 of the General Corporation Law of California. The total number of outstanding shares entitled to vote with respect to the foregoing amendment was 23,637,410 shares of Common Stock. The number of shares voting in favor of the foregoing amendment equaled or exceeded the vote required; such required vote being a majority of the outstanding shares of Common Stock.

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We further declare under penalty of perjury under the laws of the State of California that the matters set forth in this Certificate are true and correct of our own knowledge.

Date:  May 13, 1999

                                  /s/ David Goldberg
                                 ------------------------------------
                                 David Goldberg, Vice President


                                  /s/ Jack E. Corrigan
                                 ------------------------------------
                                 Jack E. Corrigan, Secretary

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Exhibit 5.1

David Goldberg
Vice President and Counsel
PS Business Parks, Inc.
701 Western Avenue
Glendale, California 91201-2397

May 17, 1999

PS Business Parks, Inc.
701 Western Avenue
Glendale, California 91201-2397

Gentlemen:

As Vice President and Counsel of PS Business Parks (the "Company"), I have examined (A) the Registration Statement on Form S-3 filed by the Company with the Securities and Exchange Commission (the "Commission") on April 20, 1998, as amended through the date hereof (File No. 333-50463) and (B) the Registration Statement on Form S-3, which is expected to be filed by the Company with the Commission on or about the date of delivery of this opinion (collectively, the "Registration Statements"), which includes a Prospectus to be used in connection with securities registered under the Registration Statements (the "Prospectus"). The Prospectus relates to the offer and sale of up to $600,000,000 stated amount of (i) shares of common stock, par value $.01 per share (the "Common Shares"),
(ii) shares of preferred stock, par value $.01 per share (the "Preferred Shares"), (iii) shares of equity stock , par value $.01 per share (the "Equity Shares"), (iv) depositary shares (the "Depositary Shares") representing a fractional interest in a Preferred Share or an Equity Share and (v) warrants (the "Warrants").

I am familiar with the proceedings taken or to be taken by the Company relating to the authorization and issuance of the Common Shares, the Preferred Shares, the Equity Shares, the Depositary Shares and the Warrants in the manner set forth in the Registration Statements. I have also examined the Company's Restated Articles of Incorporation and Restated Bylaws and have made such other investigation as I have deemed necessary in order to express the opinions contained herein.

It is my opinion that:

1. The Company is a corporation duly organized and validly existing in good standing under the laws of the State of California.

2. The Common Shares, the Preferred Shares, the Equity Shares, the Depositary Shares and the Warrants, when issued and delivered in the manner and on the terms described in the Registration Statements and payment of the agreed consideration therefor has been received by the Company, will be legally issued, fully paid and nonassessable.

I hereby consent to the reference to me under the caption "Legal Opinions" in the Registration Statements and to the filing of this opinion as an exhibit to each of the Registration Statements or amendments thereto.

Very truly yours,

/s/ DAVID GOLDBERG


DAVID GOLDBERG


[Letterhead of Hogan & Hartson L.L.P.]

Exhibit 8.1

May 17, 1999

PS Business Parks, Inc.
701 Western Avenue
Glendale, California 91201-2397

Ladies and Gentlemen:

We have acted as special tax counsel to PS Business Parks, Inc., a California corporation (the "Company"), in connection with the registration of shares of common stock, par value $.01 per share (the "Common Stock"), shares of preferred stock, par value $.01 per share (the "Preferred Stock"), shares of equity stock, par value $.01 per share (the "Equity Stock"), depositary shares representing a fractional interest in a share of Preferred Stock or Equity Stock (the "Depositary Shares") and warrants to purchase Common Stock, Preferred Stock or Equity Stock (the "Warrants") with an aggregate public offering price of up to $600,000,000, on terms to be determined at the time of offering as more fully described in the Company's Registration Statement filed with the Securities and Exchange Commission on or about the date hereof ("Registration Statement," which includes the "Prospectus"). In connection with such registration, we have been asked to provide you with an opinion regarding certain federal income tax matters related to the Company. Capitalized terms used in this letter and not otherwise defined herein have the meaning set forth in the Prospectus.

Basis for Opinions

The opinions set forth in this letter are based on our best judgment regarding the application of relevant provisions of the Internal Revenue Code of 1986, as amended (the "Code"), Treasury Regulations thereunder (including proposed and temporary Treasury Regulations), and interpretations of the foregoing as expressed in court decisions, applicable legislative history, and administrative rulings and practices of the Internal Revenue Service ("IRS") (including its practices and policies endorsed in issuing private letter rulings, which are not binding on the IRS except with respect to a taxpayer that receives such a ruling), all as of the date hereof. These provisions and interpretations are subject to change, which may or may not be retroactive in effect, that might result in material modifications of our opinions.

Our opinion does not foreclose the possibility of a contrary determination by the IRS or a court of competent jurisdiction, or of a contrary determination made by the IRS or the Treasury Department in regulations or rulings issued in the future. In this regard, although we believe that our opinions set forth herein will be sustained if challenged, an opinion of counsel


PS Business Parks, Inc.
May 17, 1999

Page 2

with respect to an issue is not binding on the IRS or the courts, and is not a guarantee that the IRS will not assert a contrary position with respect to such issue or that a court will not sustain such a position asserted by the IRS.

In rendering the following opinions, we have examined such statutes, regulations, records, agreements, certificates and other documents as we have considered necessary or appropriate as a basis for such opinions, including the following:

(1) the Prospectus;

(2) the Amended and Restated Agreement and Plan of Reorganization (the "Merger Agreement") dated as of December 17, 1997, by and among Public Storage Properties XI, Inc., American Office Park Properties, Inc., a California corporation ("AOPP") and Public Storage, Inc. ("PSI");

(3) the Agreement of Limited Partnership of PS Business Parks, L.P. (the "Operating Partnership") dated as of March 17, 1998, as amended through the date hereof;

(4) the Restated Articles of Incorporation of the Company as filed with the California Secretary of State on March 17, 1998, as amended through the date hereof (the "Articles of Incorporation");

(5) the Agreement of Contribution and Merger dated December 23, 1997, by and among AOPP, New York State Common Retirement Fund, Acquiport Two Corporation, Acquiport Three Corporation and AOPP Acquisition Corp. Three;

(6) the Common Stock Purchase Agreement, dated January 23, 1998, by and among AOPP, ABKB/La Salle Securities Limited Partnership, Harvard Private Capital Realty, Inc., Cohen & Steers Capital Management, Inc., Morgan Stanley Asset Management, certain Fidelity entities and Stanford University; and

(7) such other instruments and documents related to the organization and operation of the Company as we have deemed necessary or appropriate.

The opinions set forth in this letter also are premised on certain written representations of the Company contained in a letter dated or about the date hereof regarding the assets, operations, and activities of the Company (the "Management Representation Letter").

We have made such factual and legal inquiries, including examination of the documents set forth above, as we have deemed necessary or appropriate for purposes of our opinions. For purposes of rendering our opinions, however, we have not made an independent


PS Business Parks, Inc.
May 17, 1999

Page 3

investigation or audit of the facts set forth in the above-referenced documents, including the Prospectus and the Management Representation Letter. We consequently have relied upon your representations and assumed that the information presented in such documents or otherwise furnished to us is accurate and complete in all material respects relevant to our opinions. Without limiting the foregoing, we have not undertaken to review and determine the tax status, as a partnership for federal income tax purposes, of each limited partnership and each limited liability company in which the Company owns an interest. Instead, we have, with the Company's consent, relied upon the Company's representations, set forth in the Management Representation Letter, as to the status of these entities for federal income tax purposes. If any one or more of these entities were to be classified as an association taxable as a corporation for federal income tax purposes, and the Company were considered to own more than 10% of the voting securities of such entity, that would preclude the Company from qualifying as a "real estate investment trust" for federal income tax purposes and therefore would have a material adverse impact on the opinions set forth herein.

In our review, we have assumed, with your consent, that all of the obligations imposed by any documents on the parties thereto have been and will be performed or satisfied substantially in accordance with their terms. We also have assumed the genuineness of all signatures, the proper execution of all documents that are executed, the authenticity of all documents submitted to us as originals, the conformity to originals of documents submitted to us as copies, and the authenticity of the originals from which any copies were made. Moreover, we have assumed that the Company and the Operating Partnership have been and will continue to be operated in the manner described in the relevant partnership agreement, articles (or certificate) of incorporation or other organizational documents and in the Prospectus.

We also have assumed for the purposes of our opinions that (i) the Company is a validly organized and duly incorporated corporation under the laws of the State of California, (ii) the Operating Partnership is a duly organized and validly existing partnership under the laws of the State of California, and
(iii) AOPP made an election to be taxed as a REIT for its taxable year ended December 31, 1997, and has not revoked such election for its short taxable year ending at the effective time of the merger of AOPP with and into the Company (the "AOPP Merger") and that as of December 31, 1997, AOPP did not have any undistributed "earnings and profits" (as defined for purposes of Section 857(a)(2) of the Code) that were accumulated in a taxable year of AOPP, Acquiport Three Corporation, or any other "C corporation" prior to December 31, 1997. In the event any of the statements, representations, or assumptions upon which we have relied in rendering this opinion is incorrect or incomplete, our opinion could be adversely affected and may not be relied upon.


PS Business Parks, Inc.
May 17, 1999

Page 4

Opinions

Based upon the foregoing, and subject to the various assumptions, limitations, and qualifications set forth in this letter, we are of the opinion that:

1. The Company was organized and has operated in conformity with the requirements for qualification and taxation as a real estate investment trust ("REIT") under the Code for the taxable year ended December 31, 1998 and the Company's current organization and method of operation (as described in the Prospectus and the Management Representation Letter) will enable it to continue to meet the requirements for qualification and taxation as a REIT.

2. The statements in the Prospectus under the heading "Certain Federal Income Tax Considerations," to the extent that it describes matters of law or legal conclusions, is correct in all material respects.

An opinion of counsel merely represents counsel's best judgment with respect to the probable outcome on the merits and is not binding on the IRS or the courts. There can be no assurance that positions contrary to our opinions will not be taken by the IRS, or that a court considering the issues would not hold contrary to such opinions.

We assume no obligation to advise you of any new developments in the application and interpretation of the federal income tax laws subsequent to the date of this opinion letter, and we are not undertaking to update the opinion letter from time to time.

The Company's qualification and taxation as a REIT depends upon the Company's ability to meet on a continuing basis, through actual annual operating and other results, the various requirements under the Code and described in the Prospectus with regard to, among other things, the sources of its gross income, the composition of its assets, the level of its distributions to stockholders, and the diversity of its share ownership. Hogan & Hartson L.L.P. will not review the Company's compliance with these requirements on a continuing basis. Accordingly, no assurance can be given that the actual results of operations of the Company or the Operating Partnership, the sources of their income, the nature of their assets, the level of the Company's distributions to its shareholders and the diversity of the Company's share ownership for any given taxable year will satisfy the requirements under the Code for qualification and taxation as a REIT.

In this regard, we are expressing our opinion only as to the specific matters set forth in the numbered paragraphs under the caption "Opinions." The Company's ability to qualify as a REIT also depends upon the Company not having any "earnings and profits" accumulated in any prior taxable year of the Company or any of its predecessors. The calculation of "earnings and profits" depends upon a number of factual and legal interpretations


PS Business Parks, Inc.
May 17, 1999

Page 5

related to the activities and operations of the Company and its corporate affiliates during their entire corporate existence and is subject to review and challenge by the IRS. The Company has represented to us for purposes of our opinion that the Company does not have and has not had at the close of any prior taxable year of the Company or any of its predecessor or subsidiaries, any undistributed "earnings and profits." There can be no assurance, however, that the IRS will not examine the tax returns of the Company and its predecessors and their affiliates for all years prior to the AOPP Merger and propose adjustments to increase their taxable income, which could result in the Company being considered to have undistributed "earnings and profits" at the close of its taxable year commencing January 1, 1997, in which event there could be no assurance the Company would qualify as a REIT for such year and possibly subsequent years.

We note that the Prospectus does not currently address the federal income tax considerations that may be relevant to a holder of the Preferred Stock, the Equity Stock, the Warrants or the Depositary Shares. It is our understanding that in the event the Company issues Preferred Stock, Equity Stock, Warrants, or Depositary Shares the Company will prepare a supplement to the Prospectus, which supplement will address the federal income tax considerations that are likely to be material to a holder of such securities.

This opinion letter has been prepared solely for your benefit in connection with the filing of the Registration Statement. This opinion may not be used or relied upon by any other person or for any other purpose and may not be disclosed, quoted, or filed with a governmental agency or otherwise referred to without our prior written consent. We hereby consent to the filing of this opinion letter as Exhibit 8.1 to the Registration Statement and to the reference to this firm under the caption "Legal Matters" in the Prospectus. In giving this consent, we do not thereby admit that we are an "expert" within the meaning of the Securities Act of 1933, as amended.

Very truly yours,

/s/ Hogan & Hartson L.L.P.


HOGAN & HARTSON L.L.P.


EXHIBIT 23.1

CONSENT OF ERNST & YOUNG LLP

We consent to the reference to our firm under the caption "Experts" in the Prospectus of PS Business Parks, Inc. (included in the Registration Statement on Form S-3 (No. 333-_____)) and which will also be used in connection with the Registration Statement on Form S-3 (No. 333-50463) for the registration of shares of its common stock, its preferred stock, its equity stock, its depositary shares and warrants for the purchase of its common stock, preferred stock and equity stock and to the incorporation by reference therein of our report dated February 2, 1999 with respect to the consolidated financial statements and schedule of PS Business Parks, Inc. in its Annual Report on Form 10-K for the year ended December 31, 1998.

                                          /s/ Ernst & Young LLP

Los Angeles, California


May 17, 1999