Exhibit 1.1

Execution Version

36,500,000 Shares

CROWN CASTLE INTERNATIONAL CORP.

COMMON STOCK, PAR VALUE $0.01 PER SHARE

UNDERWRITING AGREEMENT

July 20, 2017

July 20, 2017

Morgan Stanley & Co. LLC

1585 Broadway

New York, NY 10036

Merrill Lynch, Pierce, Fenner & Smith

Incorporated

One Bryant Park

New York, NY 10036

J.P. Morgan Securities LLC

383 Madison Avenue

New York, NY 10179

as Representatives for the Underwriters

 named in Schedule I hereto

Ladies and Gentlemen:

Crown Castle International Corp., a Delaware corporation (the “ Company ”), proposes to issue and sell to you, the several underwriters named in Schedule I hereto (the “ Underwriters ”), for whom you are acting as representatives (“ Representatives ”), 36,500,000 shares of its common stock, par value $0.01 per share (the “ Firm Shares ”). The Company also proposes to issue and sell to the several Underwriters not more than an additional 3,650,000 shares of its common stock, par value $0.01 per share (the “ Additional Shares ”), if and to the extent that you, as Representatives of the offering, shall have determined to exercise, on behalf of the Underwriters, the right to purchase such shares of common stock granted to the Underwriters in Section 2 hereof. The Firm Shares and the Additional Shares are hereinafter collectively referred to as the “ Shares .” The shares of common stock, par value $0.01 per share, of the Company to be outstanding after giving effect to the sales contemplated hereby are hereinafter referred to as the “ Common Stock .”

The Company has filed with the Securities and Exchange Commission (the “ Commission ”) a registration statement, including a prospectus, on Form S-3 (No. 333-203074), relating to securities (the “ Shelf Securities ”), including the Shares, to be issued from time to time thereunder by the Company. The registration statement, as amended to the date of this Agreement, including the information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A or Rule 430B under the Securities Act of 1933, as amended (the “ Securities Act ”), is hereinafter referred to as the “ Registration Statement ,” and the related prospectus covering the Shelf Securities dated March 27, 2015, in the form first used to confirm sales of the Shares (or in the form first made available to the Underwriters by the

Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Basic Prospectus .” The Basic Prospectus, as supplemented by the prospectus supplement specifically relating to the Shares in the form first used to confirm sales of the Shares (or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Prospectus ,” and the term “ preliminary prospectus ” means any preliminary form of the Prospectus. For purposes of this Agreement, “ free writing prospectus ” has the meaning set forth in Rule 405 under the Securities Act, “ Time of Sale Prospectus ” means the documents set forth opposite the caption “Time of Sale Prospectus” in Schedule II hereto and the information identified on Schedule II-A hereto, and “ road show ” means a “bona fide electronic road show” as defined in Rule 433(h)(5) under the Securities Act. As used herein, the terms “Registration Statement,” “Basic Prospectus,” “preliminary prospectus,” “Time of Sale Prospectus” and “Prospectus” shall include the documents, if any, incorporated by reference therein. The terms “ supplement ,” “ amendment ,” and “ amend ” as used herein with respect to the Registration Statement, the Basic Prospectus, the Time of Sale Prospectus, any preliminary prospectus, any free writing prospectus or the Prospectus shall include all documents subsequently filed by the Company with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), that are deemed to be incorporated by reference therein.

1. Representations and Warranties of the Company . The Company represents and warrants to and agrees with each of the Underwriters that:

(a) The Registration Statement has become effective; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company, threatened by the Commission. The Registration Statement is an automatic shelf registration statement as defined in Rule 405 under the Securities Act, and the Company is a well-known seasoned issuer (as defined in Rule 405 under the Securities Act) eligible to use the Registration Statement as an automatic shelf registration statement, and the Company has not received notice that the Commission objects to the use of the Registration Statement as an automatic shelf registration statement.

(b) (i) Each document, if any, filed or to be filed pursuant to the Exchange Act and incorporated by reference in the Time of Sale Prospectus or the Prospectus complied or will comply when so filed in all material respects with the Exchange Act and the applicable rules and regulations of the Commission thereunder, (ii) each part of the Registration Statement, when such part became effective, did not contain, and each such part, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iii) the Registration Statement does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iv) the Registration Statement, as of the date hereof, complies, and the Prospectus, as of its date, will comply, and the Registration Statement and the Prospectus, as amended or supplemented, if applicable, will comply, as of the Closing Date (as defined in Section 4), in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder, (v) the Time of Sale Prospectus does not, and at the time of each sale of the Shares in connection with the offering when the Prospectus is not yet available to prospective purchasers and at the Closing Date, the Time of Sale Prospectus, as then amended or

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supplemented by the Company, if applicable, will not, contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, (vi) each road show, if any, when considered together with the Time of Sale Prospectus, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading and (vii) the Prospectus, as of its date, will not contain and, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that the representations and warranties set forth in this paragraph do not apply to statements or omissions in the Registration Statement, the Time of Sale Prospectus or the Prospectus based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein, which is set forth in Section 9(b) hereof.

(c) The Company is not an “ineligible issuer” in connection with the offering pursuant to Rules 164, 405 and 433 under the Securities Act. Any free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Each free writing prospectus that the Company has filed, or is required to file, in connection with the offering of Shares pursuant to Rule 433(d) under the Securities Act or that was prepared by or on behalf of or used or referred to by the Company complies, or will comply, in all material respects with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Except for the free writing prospectuses, if any, identified in Schedule II hereto forming part of the Time of Sale Prospectus, and road shows, if any, each furnished to you before first use, the Company has not prepared, used or referred to, and will not, without your prior consent, prepare, use or refer to, any free writing prospectus.

(d) Neither the Company nor any of its subsidiaries has sustained, since the date of the latest audited financial statements incorporated by reference into the Registration Statement, the Time of Sale Prospectus or the Prospectus, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the Time of Sale Prospectus and the Prospectus or as would not reasonably be expected, in the aggregate, to result in a Material Adverse Effect (as defined below); and, since the respective dates as of which information is given in the Time of Sale Prospectus and the Prospectus, there has not been any change in the capital stock or long-term debt of the Company or any of its subsidiaries or any material adverse change, or any development involving a prospective material adverse change, except such as are described in the Time of Sale Prospectus and the Prospectus or such as would not be reasonably expected, in the aggregate, to result in a material adverse effect on the condition (financial or other), business, properties or results of operations of the Company and the Material Subsidiaries (as defined below), taken as a whole (a “ Material Adverse Effect ”). As of the date hereof, each subsidiary of the Company that constitutes a “ significant subsidiary ,” as such term is defined in Rule 405 of the rules and regulations under the Securities Act, is a “ Material Subsidiary ” and, collectively, comprise the “ Material Subsidiaries .”

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(e) (i) The Company and each of its subsidiaries have (1) good and marketable fee or leasehold title, as applicable, to all real property owned or leased by them and (2) good and marketable title to all personal property owned by them; and (ii) any other personal property leased or held by the Company or any of its subsidiaries pursuant to any licenses, easements, management agreements, other contracts or occupancy agreements or otherwise is leased or held under valid, subsisting and enforceable agreements, in each case free and clear of all liens, encumbrances and defects except such as are described in the Time of Sale Prospectus and the Prospectus or would not reasonably be expected, in the aggregate, to have a Material Adverse Effect.

(f) The Company is a corporation duly incorporated and validly existing and in good standing under the laws of the State of Delaware with all requisite corporate power and authority to own, lease and operate its properties and to conduct its business as described in the Time of Sale Prospectus and the Prospectus, and is duly registered and qualified to conduct its business and is in good standing in each jurisdiction or place where the nature of its properties or the conduct of its business requires such registration or qualification, except where the failure so to register or qualify or to be in good standing would not have a Material Adverse Effect; and each Material Subsidiary of the Company has been duly incorporated or formed, as the case may be, and is validly existing as a corporation, limited partnership, limited liability company or other legal entity in good standing or the equivalent under the laws of its jurisdiction of incorporation or formation, as the case may be.

(g) The Company has an authorized capitalization as set forth in the Time of Sale Prospectus and the Prospectus, and all the shares of Common Stock outstanding prior to the issuance of the Shares have been duly authorized and are validly issued, fully paid and non-assessable, and conform to the description of the Common Stock contained in the Time of Sale Prospectus and the Prospectus; and all of the issued shares of capital stock of each Material Subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims, except as set forth in the Time of Sale Prospectus and the Prospectus.

(h) Neither the Company nor any of its subsidiaries, nor, to the knowledge of the Company, any of their respective affiliates, has taken any action which is designed to or which has constituted or which might have been reasonably expected to cause or result in stabilization or manipulation of the price of any security of the Company in connection with the offering of the Shares.

(i) No “nationally recognized statistical rating organization” (as such term is defined for purposes of Section 3(a)(62) under the Exchange Act) has imposed any condition (financial or otherwise) on the Company or any of its subsidiaries relating to any rating assigned to the Company or any such subsidiary or to any securities of the Company or any such subsidiary.

(j) The Shares have been duly authorized and, when issued and delivered in accordance with the terms of this Agreement, will be validly issued, fully paid and non-assessable, and the issuance of such Shares will not be subject to any preemptive or similar rights.

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(k) The execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement will not conflict with, or result in a breach or violation of, any of the terms or provisions of or, with the giving of notice or the lapse of time or both, constitute a default under (A) any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (B) the provisions of the charter, by-laws or other constitutive documents of the Company or any of its subsidiaries or (C) any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets except in the cases of clause (A) or (C), such breaches, violations or defaults that in the aggregate would not have a Material Adverse Effect; and no consent, approval, authorization, order, registration or qualification of or with any such court or governmental agency or body is required for the performance by the Company of its obligations under this Agreement, except where the failure to obtain or make such consents, approvals, authorizations, registrations or qualifications would not, individually or in the aggregate, have a Material Adverse Effect.

(l) (A) Neither the Company nor any of its Material Subsidiaries is in violation of its charter, by-laws or other constitutive documents, (B) neither the Company nor any of its subsidiaries is in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any material indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which it is a party or by which it is bound or to which any of its properties or assets is subject or (C) neither the Company nor any of its subsidiaries is in violation of any law, ordinance, governmental rule, regulation or court decree to which it or its property or assets may be subject or has failed to obtain any material license, permit, certificate, franchise or other governmental authorization or permit necessary to the ownership of its property or to the conduct of its business, except for, in the cases of clause (B) or (C), such defaults, violations or failures to obtain that in the aggregate would not have a Material Adverse Effect.

(m) The statements contained in (A) the Time of Sale Prospectus and the Prospectus under the captions “Description of Capital Stock” and “Material United States Federal Income Tax Considerations” and (B) the Prospectus under the caption “Underwriting,” insofar as they are descriptions of contracts, agreements or other legal documents, or refer to statements of law or legal conclusions, are accurate in all material respects and present fairly the information purported to be described therein.

(n) Other than as set forth in the Time of Sale Prospectus and the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

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(o) Each preliminary prospectus filed as part of the Registration Statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 under the Securities Act, complied when so filed in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder.

(p) The Company is not, and after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Prospectus will not be, required to register as an “investment company” as such term is defined in the Investment Company Act of 1940, as amended.

(q) There has been no storage, disposal, generation, manufacture, refinement, transportation, handling or treatment of toxic wastes, medical wastes, hazardous wastes or hazardous substances by the Company or any of its subsidiaries (or, to the knowledge of the Company, any of their predecessors in interest) at, upon or from any of the property now or previously owned or leased by the Company or any of its subsidiaries in violation of any applicable law, ordinance, rule, regulation, order, judgment, decree or permit or which would require remedial action under any applicable law, ordinance, rule, regulation, order, judgment, decree or permit, except for any violation or remedial action which would not have, or could not be reasonably likely to have, singularly or in the aggregate, a Material Adverse Effect; there has been no material spill, discharge, leak, emission, injection, escape, dumping or release of any kind onto such property or into the environment surrounding such property of any toxic wastes, medical wastes, solid wastes, hazardous wastes or hazardous substances due to or caused by the Company or any of its subsidiaries or with respect to which the Company or any of its subsidiaries has knowledge, except for any such spill, discharge, leak, emission, injection, escape, dumping or release which would not have or would not be reasonably likely to have, singularly or in the aggregate, a Material Adverse Effect; and the terms “hazardous wastes,” “toxic wastes,” “hazardous substances” and “medical wastes” shall have the meanings specified in any applicable local, state, federal and foreign laws or regulations with respect to environmental protection.

(r) Except as set forth in the Registration Statement, the Time of Sale Prospectus and the Prospectus, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Securities Act with respect to any securities of the Company or to require the Company to include such securities with the Shares registered pursuant to the Registration Statement.

(s) PricewaterhouseCoopers LLP, who has certified certain financial statements of the Company and its subsidiaries, are independent public accountants with respect to the Company as required by the Securities Act and the rules and regulations of the Commission thereunder and the rules and regulations of the Public Company Accounting Oversight Board.

(t) To the knowledge of the Company, Deloitte & Touche LLP, who has certified the consolidated financial statements of LTS Group Holdings LLC (“ Target ”) as of and for the year ended December 31, 2016 incorporated by reference in the Time of Sale Prospectus and the Prospectus, were independent public accountants with respect to Target as defined by the Securities Act and the rules and regulations of the Commission thereunder.

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(u) To the knowledge of the Company, the Consolidated Statement of Income of the Target fairly presents the revenues and certain expenses relating to the Target for the respective periods indicated, in each case in accordance with generally accepted accounting principles consistently applied throughout such periods.

(v) The Company has all requisite corporate power and authority to execute and deliver this Agreement and to otherwise perform its obligations under this Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(w) The Company’s consolidated historical financial statements, together with the related notes thereto, incorporated by reference into the Time of Sale Prospectus and the Prospectus, comply as to form in all material respects with the applicable requirements of Regulation S-X under the Securities Act. Such consolidated historical financial statements fairly present the financial position of the Company at the respective dates indicated and the results of operations and cash flows for the respective periods indicated, in each case in accordance with generally accepted accounting principles consistently applied throughout such periods. The other financial and statistical information and data incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus (other than the estimated financial and statistical information and data related to the Lightower Acquisition (as defined in the Time of Sale Prospectus and Prospectus)) is, in all material respects, fairly presented and prepared on a basis consistent with the financial statements and the books and records of the Company. The interactive data in eXtensible Business Reporting Language incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus fairly presents the information called for and is prepared in accordance with the Commission’s rules and guidance applicable thereto, in each case, in all material respects. The estimated financial and statistical information and data relating to the Lightower Acquisition included in the Time of Sale Prospectus and the Prospectus were prepared in good faith, are reasonable in the good faith judgment of the Company and are based on or derived from sources that the Company believes to be reliable for the purpose of preparing such estimates.

(x) The Company and each of the Material Subsidiaries has such permits, licenses, franchises, registrations and other approvals or authorizations of any governmental or regulatory authority (“ Permits ”), including, without limitation, any permits required by the Federal Communications Commission (“ FCC ”) or the Federal Aviation Administration, as are necessary under applicable law to own their respective properties and to conduct their respective businesses in the manner described in the Time of Sale Prospectus and the Prospectus, except to the extent that the failure to have such Permits would not have a Material Adverse Effect. The Company and the Material Subsidiaries have fulfilled and performed, in all material respects, all of their respective obligations with respect to the Permits, and no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other impairment of the rights of, or imposition of a penalty on, the holder of any such Permit, subject in each case to such qualification as may be set forth in the Time of Sale Prospectus and the Prospectus and except to the extent that any such revocation, termination, impairment or penalty would not have a Material Adverse Effect. Except as described in the Time of Sale Prospectus and the Prospectus, none of the Permits contains any restriction that has not previously been satisfied and that is materially burdensome to the Company or any of the Material Subsidiaries.

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(y) For each existing tower of the Company not yet registered with the FCC where registration will be required, the FCC’s grant of an application for registration of such tower will not have a significant environmental effect as defined under Section 1.1307(a) or (b) of the FCC’s rules.

(z) The consummation of the transactions contemplated by this Agreement shall not cause any third party to have any rights of first refusal with respect to the acquisition of towers of the Company or any of its subsidiaries under any agreement filed as an exhibit to any document incorporated by reference in the Prospectus (the “ Material Agreements ”) that has not already been described in the Time of Sale Prospectus and the Prospectus as to which the Company and any of the Material Subsidiaries or any of their property or assets may be subject.

(aa) The Company and each of the Material Subsidiaries owns or possesses all patents, trademarks, trademark registrations, service marks, service mark registrations, trade names, copyrights, licenses, inventions, trade secrets and rights described in the Time of Sale Prospectus and the Prospectus as being owned by any of them or necessary for the conduct of their respective businesses, and neither the Company nor any of the Material Subsidiaries is aware of any claim to the contrary or any challenge by any other person to the rights of the Company or any of the Material Subsidiaries with respect to such rights that, if determined adversely to the Company or any such Material Subsidiary, would individually or in the aggregate have a Material Adverse Effect.

(bb) Neither the Company nor any of its subsidiaries is involved in any strike, job action or labor dispute with any group of employees, and, to the knowledge of the Company and its subsidiaries, no such action or dispute is threatened.

(cc) The Company and each of its subsidiaries are in compliance in all material respects with all presently applicable provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder (“ ERISA ”); no “reportable event” (as defined in ERISA) has occurred with respect to any “pension plan” (as defined in ERISA) for which the Company would have any liability; the Company has not incurred and does not expect to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any “pension plan” or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the “ Code ”); and each “pension plan” for which the Company would have any liability that is intended to be qualified under Section 401(a) of the Code is so qualified in all material respects and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification.

(dd) The Company and each of its subsidiaries have filed all federal, state and local income and franchise tax returns required to be filed through the date hereof and have paid all taxes required to be paid to the extent due and payable, except to the extent any such taxes are currently being contested in good faith, and no tax deficiency has been determined adversely to the Company or any of its subsidiaries nor does the Company or any of its subsidiaries have any knowledge of any tax deficiency, except where such failure to file such tax return or pay such tax deficiency (if determined adversely to the Company or any of its subsidiaries) would not have a Material Adverse Effect.

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(ee) The Company operates in conformity with the requirements for qualification and taxation as a “real estate investment trust” (a “ REIT ”) under Sections 856 through 860 of the Code; and the method of operation for the Company and its subsidiaries as described in the Prospectus will enable the Company to meet the requirements for qualification and taxation as a REIT under the Code.

(ff) The Company (i) makes and keeps accurate books and records and (ii) maintains a system of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) to provide reasonable assurance that (A) transactions are executed in accordance with management’s authorization, (B) transactions are recorded as necessary to permit preparation of its financial statements in conformity with generally accepted accounting principles and to maintain accountability for assets, (C) access to its financial assets is permitted only in accordance with management’s general or specific authorization, (D) the reported accountability for its assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences and (E) the interactive data in eXtensible Business Reporting Language incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus is, in all material respects, prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(gg) The Company and each of the Material Subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as is adequate for the conduct of its businesses and the value of its properties and as is customary for companies engaged in similar businesses in similar industries.

(hh) The Company has established and maintains disclosure controls and procedures (as such term is defined in Rule 13a-14 and 15d-14 under the Exchange Act); such disclosure controls and procedures are designed to ensure that material information relating to the Company, including its consolidated subsidiaries, is made known to the Company’s Chief Executive Officer and its Chief Financial Officer by others within those entities, and such disclosure controls and procedures are effective to perform the functions for which they were established; the Company’s auditors and the Audit Committee of the Board of Directors have been advised of: (A) any significant deficiencies in the design or operation of internal controls which could adversely affect the Company’s ability to record, process, summarize, and report financial data; and (B) any fraud, whether or not material, that involves management or other employees who have a role in the Company’s internal controls; any material weaknesses in internal controls have been identified for the Company’s auditors; and since the date of the most recent evaluation of such disclosure controls and procedures, there have been no significant changes in internal controls or in other factors that could significantly affect internal controls, including any corrective actions with regard to significant deficiencies and material weaknesses.

(ii) There is and has been no failure on the part of the Company and any of the Company’s directors or officers, in their capacities as such, to comply with the provisions of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith.

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(jj) Neither the Company or any of its subsidiaries, nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate or other person acting on behalf of the Company or any of its subsidiaries, has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “ FCPA ”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA; (iii) violated or is in violation of any provision of the FCPA, or any applicable law or regulation implementing the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, or committed an offence under the Bribery Act 2010 of the United Kingdom, or any other applicable anti-bribery or anti-corruption law; or (iv) made, offered, agreed, requested or taken an act in furtherance of any unlawful bribe or provided an unlawful benefit, including, without limitation, any rebate, payoff, influence payment, kickback or other unlawful payment or benefit. The Company and its subsidiaries have instituted, maintain and enforce, and reasonably expect to continue to maintain and enforce, policies and procedures designed to ensure compliance with applicable anti-bribery and anti-corruption laws.

(kk) The operations of the Company and its subsidiaries are and have been conducted at all times in material compliance with all applicable financial recordkeeping and reporting requirements, including those of the Currency and Foreign Transactions Reporting Act of 1970, as amended by Title III of the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001 (USA PATRIOT Act), and the applicable money laundering statutes of all jurisdictions where the Company or any of its subsidiaries conduct business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “ Anti-Money Laundering Laws ”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(ll) Neither the Company or any of its subsidiaries, nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate or other person acting on behalf of the Company or any of its subsidiaries, is currently the subject or the target of any sanctions administered or enforced by the U.S. government (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury or the U.S. Department of State and including, without limitation, the designation as a “specially designated national” or “blocked person”), the United Nations Security Council, the European Union, Her Majesty’s Treasury, or other relevant sanctions authority (collectively, “ Sanctions ”), nor is any of the Company or any of its subsidiaries located, organized or resident in a country or territory that is the subject or target of Sanctions, including, without limitation, Crimea, Cuba, Iran, North Korea, Sudan and Syria (each, a “ Sanctioned Country ”); and the Company will not directly or indirectly use the proceeds of the offering of the Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity (i) to fund or facilitate any activities of or conduct business with any person that, at the time of such funding or facilitation, is the subject or target of Sanctions or (ii) to fund or facilitate any activities of or conduct business in any Sanctioned Country.

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2. Agreements to Sell and Purchase . The Company hereby agrees to sell to the several Underwriters, and each Underwriter, upon the basis of the representations and warranties herein contained, but subject to the conditions hereinafter stated, agrees, severally and not jointly, to purchase from the Company at $93.60 a share (the “ Purchase Price ”) the number of Firm Shares set forth in Schedule I hereto opposite the name of such Underwriter.

On the basis of the representations and warranties contained in this Agreement, and subject to its terms and conditions, the Company agrees to sell to the Underwriters the Additional Shares, and the Underwriters shall have the right to purchase, severally and not jointly, up to 3,650,000 Additional Shares at the Purchase Price, provided, however, that the amount per share paid by the Underwriters for any Additional Shares shall be reduced by an amount per share equal to any dividends declared by the Company and payable on the Firm Shares but not payable on such Additional Shares. The Representatives may exercise this right on behalf of the Underwriters in whole or from time to time in part by giving written notice not later than 30 days after the date of this Agreement. Any exercise notice shall specify the number of Additional Shares to be purchased by the Underwriters and the date on which such shares are to be purchased. Each purchase date must be at least one business day after the written notice is given and may not be earlier than the closing date for the Firm Shares nor later than ten business days after the date of such notice. Additional Shares may be purchased as provided in Section 4 hereof. On each day, if any, that Additional Shares are to be purchased (an “ Option Closing Date ”), each Underwriter agrees, severally and not jointly, to purchase the number of Additional Shares (subject to such adjustments to eliminate fractional shares as you may determine) that bears the same proportion to the total number of Additional Shares to be purchased on such Option Closing Date as the number of Firm Shares set forth in Schedule I hereto opposite the name of such Underwriter bears to the total number of Firm Shares.

The Company also covenants with each Underwriter that, without the prior written consent of the Representatives on behalf of the Underwriters, it will not, during the period ending 60 days after the date of the Prospectus, (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (3) file any registration statement with the Commission relating to the offering of any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock.

The restrictions contained in the preceding paragraph shall not apply to (a) the Common Stock to be sold hereunder, (b) the issuance by the Company of Common Stock upon the exercise of an option or warrant or the conversion of a security outstanding on the date hereof of which the Underwriters have been advised in writing or which has been disclosed in the Time of Sale Prospectus, (c) the issuance by the Company or any of its subsidiaries of equity awards

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pursuant to employee benefit plans described in the Time of Sale Prospectus (including Common Stock issued under any such equity awards upon vesting), (d) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of Common Stock, provided that (i) such plan does not provide for the transfer of Common Stock during the 60-day restricted period and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is required of or voluntarily made by or on behalf of the Company regarding the establishment of such plan, such announcement or filing shall include a statement to the effect that no transfer of Common Stock may be made under such plan during the 60-day restricted period, (e) the filing of one or more registration statements on Form S-8 with the Commission with respect to the Common Stock issued or issuable under any employee benefit plan described in the Time of Sale Prospectus, (f) the issuance by the Company of 6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share (the “ Preferred Stock ”), and the issuance, if any, of Common Stock upon the conversion of any of the Preferred Stock, or (g) the issuance of securities in connection with joint ventures, commercial relationships or other strategic transactions; provided that, in the case of this clause (g), (i) the aggregate number of shares of the Common Stock to be issued in all such transactions referenced in this clause (g) does not exceed 10% of the outstanding Common Stock immediately following the offering and (ii) the recipient thereof enters into a lock-up letter substantially in the form of Exhibit A hereto with respect to the remaining 60-day restricted period.

3. Public Offering . The Company is advised by you that the Underwriters propose to make a public offering of their respective portions of the Shares as soon after this Agreement has become effective as in your judgment is advisable. The Company is further advised by you that the Shares are to be offered to the public upon the terms set forth in the Prospectus.

4. Payment and Delivery. Payment for the Firm Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Firm Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on July 26, 2017, or at such other time on the same or such other date, not later than August 2, 2017, as shall be designated in writing by you. The time and date of such payment are hereinafter referred to as the “ Closing Date .”

Payment for any Additional Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Additional Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on the date specified in the corresponding notice described in Section 2 or at such other time on the same or on such other date, in any event not later than August 25, 2017, as shall be designated in writing by the Representatives.

The Firm Shares and Additional Shares shall be registered in such names and in such denominations as you shall request in writing not later than one full business day prior to the Closing Date or the applicable Option Closing Date, as the case may be. The Firm Shares and Additional Shares shall be delivered to you on the Closing Date or an Option Closing Date, as the case may be, for the respective accounts of the several Underwriters, with any transfer taxes payable in connection with the transfer of the Shares to the Underwriters duly paid, against payment of the Purchase Price therefor.

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5. Conditions . (I) The obligations of the Company to sell the Shares to the Underwriters and the several obligations of the Underwriters to purchase and pay for the Shares on the Closing Date are subject to the condition that the Prospectus, as amended or supplemented, in relation to the Shares, shall have been filed with the Commission pursuant to Rule 424(b) within the applicable time period described for such filing by the rules and regulations under the Securities Act, and as of the Closing Date and each Option Closing Date, no stop order suspending the effectiveness of the Registration Statement shall be in effect or shall be pending or, to the knowledge of the Company, threatened by the Commission; and no notice objecting to its use pursuant to Rule 401(g)(2) shall have been issued and no proceeding for such purpose or pursuant to Section 8A of the Securities Act shall have been instituted or threatened.

The several obligations of the Underwriters are subject to the following further conditions:

(a) Subsequent to the execution and delivery of this Agreement and prior to the Closing Date:

(i) there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded any of the securities of the Company or any of its subsidiaries by any “nationally recognized statistical rating organization,” as such term is defined for purposes of Section 3(a)(62) under the Exchange Act; and

(ii) there shall not have occurred any change, or any development involving a prospective change, in the condition, financial or otherwise, or in the earnings, business or operations of the Company and its subsidiaries, taken as a whole, from that set forth in the Time of Sale Prospectus as of the date of this Agreement that, in the Underwriters’ judgment, is material and adverse and that makes it, in the Underwriters’ judgment, impracticable to market the Shares on the terms and in the manner contemplated in the Time of Sale Prospectus.

(b) The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by an executive officer of the Company, to the effect set forth in Section 5(I)(a)(i) above and to the effect that the representations and warranties of the Company contained in this Agreement are true and correct as of the Closing Date and that the Company has complied with all of the agreements and satisfied all of the conditions on its part to be performed or satisfied hereunder on or before the Closing Date.

Any officer signing and delivering such certificate may rely upon the best of his or her knowledge as to proceedings threatened.

(c) The Underwriters shall have received on the Closing Date an opinion, including an opinion with regard to the Company’s qualification and taxation as a REIT, and a negative assurance letter of Cravath, Swaine & Moore LLP, outside counsel for the Company, each dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

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(d) The Underwriters shall have received on the Closing Date an opinion of Skadden, Arps, Slate, Meagher & Flom LLP, tax counsel for the Company, with regard to the Company’s qualification and taxation as a REIT, dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(e) The Underwriters shall have received on the Closing Date an opinion of the General Counsel or Associate General Counsel to the Company, dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(f) The Underwriters shall have received on the Closing Date an opinion and a negative assurance letter of Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the Underwriters, each dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(g) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from PricewaterhouseCoopers LLP, independent public accountants, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in the Registration Statement, the Time of Sale Prospectus and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than three business days prior to the Closing Date.

(h) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from Deloitte & Touche LLP, independent public accountants to Target, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the consolidated financial statements of Target as of and for the year ended December 31, 2016 contained in the Time of Sale Prospectus and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than three business days prior to the Closing Date.

(i) The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and the officers and directors of the Company listed in Exhibit B hereto relating to sales and certain other dispositions of shares of Common Stock or certain other securities, delivered to you on or before the date hereof, shall be in full force and effect on the Closing Date.

(j) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from Daniel K. Schlanger, Senior Vice President and Chief Financial Officer of the Company, substantially in the form of Exhibit C hereto.

(k) The Shares shall have been approved for listing on the New York Stock Exchange (“ NYSE ”), subject only to official notice of issuance.

(l) On or prior to the Closing Date, the Company shall have furnished to the Representatives such further certificates and documents as the Representatives may reasonably request.

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(m) The representations and warranties of the Company contained herein shall be true and correct on and as of the Closing Date.

(II) The several obligations of the Underwriters to purchase Additional Shares hereunder are subject to the delivery to you on the applicable Option Closing Date of the following:

(a) a certificate, dated the Option Closing Date and signed by an executive officer of the Company, confirming that the certificate delivered on the Closing Date pursuant to Section 5(I)(b) hereof remains true and correct as of such Option Closing Date;

(b) an opinion, including an opinion with regard to the Company’s qualification and taxation as a REIT, and a negative assurance letter of Cravath, Swaine & Moore LLP, outside counsel for the Company, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(c) hereof;

(c) an opinion of Skadden, Arps, Slate, Meagher & Flom LLP, tax counsel for the Company, with regard to the Company’s qualification and taxation as a REIT, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(d) hereof;

(d) an opinion of the General Counsel or Associate General Counsel to the Company, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Options Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(e);

(e) an opinion and a negative assurance letter of Skadden, Arps, Slate, Meagher & Flom, LLP, counsel for the Underwriters, each dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(f) hereof;

(f) a letter dated the Option Closing Date, in form and substance satisfactory to the Underwriters, from PricewaterhouseCoopers LLP, independent public accountants, substantially in the same form and substance as the letter furnished to the Underwriters pursuant to Section 5(I)(g) hereof; provided that the letter delivered on the Option Closing Date shall use a “cut-off date” not earlier than three business days prior to such Option Closing Date;

(g) a letter dated the Option Closing Date, in form and substance satisfactory to the Underwriters, from Deloitte & Touche LLP, independent public accountants, substantially in the same form and substance as the letter furnished to the Underwriters pursuant to Section 5(I)(h) hereof; provided that the letter delivered on the Option Closing Date shall use a “cut-off date” not earlier than three business days prior to such Option Closing Date;

(h) such other documents as you may reasonably request with respect to the good standing of the Company, the due authorization and issuance of the Additional Shares to be sold on such Option Closing Date and other matters related to the issuance of such Additional Shares; and

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(i) The representations and warranties of the Company contained herein shall be true and correct on and as of the Option Closing Date.

6. Covenants of the Company . The Company covenants with each Underwriter as follows:

(a) To furnish to you, without charge, a signed copy of the Registration Statement (including exhibits thereto and documents incorporated by reference therein) and to deliver to each of the Underwriters during the period mentioned in Section 6(e) or 6(f) below, as many copies of the Time of Sale Prospectus, the Prospectus, any documents incorporated by reference therein and any supplements and amendments thereto or to the Registration Statement as you may reasonably request. The Company will promptly advise the Underwriters of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any notice objecting to its use or the institution or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act or of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act.

(b) Prior to the completion of this offering, before amending or supplementing the Registration Statement, the Time of Sale Prospectus or the Prospectus, to furnish to you a copy of each such proposed amendment or supplement and not to file any such proposed amendment or supplement to which you reasonably object promptly after receipt thereof, provided that, if in the reasonable opinion of counsel for the Company, any such amendment or supplement shall be required by law or regulation to be used, that the Company shall be permitted to file such amendment or supplement after taking into account such comments as you may reasonably make on the content, form or other aspects of such amendment or supplement, and to file with the Commission within the applicable period specified in Rule 424(b) under the Securities Act any prospectus required to be filed pursuant to such Rule.

(c) To furnish to you a copy of each proposed free writing prospectus to be prepared by or on behalf of, used by, or referred to by the Company and not to use or refer to any proposed free writing prospectus to which you reasonably object, provided that, if in the reasonable opinion of counsel for the Company, any such amendment or supplement shall be required by law or regulation to be used, that the Company shall be permitted to file such amendment or supplement after taking into account such comments as you may reasonably make on the content, form or other aspects of such amendment or supplement.

(d) Not to take any action that would result in an Underwriter being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of the Underwriter that the Underwriter otherwise would not have been required to file thereunder.

(e) If the Time of Sale Prospectus is being used to solicit offers to buy the Shares at a time when the Prospectus is not yet available to prospective purchasers and any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Time of Sale Prospectus in order to make the statements therein, in the light of the circumstances, not misleading, or if any event shall occur or condition exist as a result of which the Time of Sale

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Prospectus conflicts with the information contained in the Registration Statement then on file, or if, in the reasonable opinion of counsel for the Underwriters, it is necessary to amend or supplement the Time of Sale Prospectus to comply with applicable law, forthwith to prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to the dealers (whose names and addresses you will furnish to the Company) to which Shares may have been sold by you on behalf of the Underwriters, either amendments or supplements to the Time of Sale Prospectus so that the statements in the Time of Sale Prospectus as so amended or supplemented will not, in the light of the circumstances when the Time of Sale Prospectus is delivered to a prospective purchaser, be misleading or so that the Time of Sale Prospectus, as amended or supplemented, will no longer conflict with the Registration Statement, or so that the Time of Sale Prospectus, as amended or supplemented, will comply with applicable law.

(f) If, during such period after the first date of the public offering of the Shares as in the reasonable opinion of counsel for the Underwriters, the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is required by law to be delivered in connection with sales by an Underwriter or dealer, any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Prospectus in order to make the statements therein, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is delivered to a purchaser, not misleading, or if, in the reasonable opinion of counsel for the Underwriters, it is necessary to amend or supplement the Prospectus to comply with applicable law, forthwith to prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to the dealers (whose names and addresses you will furnish to the Company) to which Shares may have been sold by you on behalf of the Underwriters and to any other dealers upon request, either amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is delivered to a purchaser, be misleading or so that the Prospectus, as amended or supplemented, will comply with applicable law.

(g) To endeavor to qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as you shall reasonably request; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction where it is not presently qualified or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(h) To apply the net proceeds from the sale of the Shares as described in each of the Time of Sale Prospectus and the Prospectus under the heading “Use of Proceeds.”

(i) To make generally available to the Company’s security holders and to you as soon as practicable an earnings statement covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the date of this Agreement which shall satisfy the provisions of Section 11(a) of the Securities Act and the rules and regulations of the Commission thereunder.

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(j) If the third anniversary of the initial effective date of the Registration Statement occurs before all the Shares have been sold by the Underwriters, prior to the third anniversary to file a new shelf registration statement and to take any other action necessary to permit the public offering of the Shares to continue without interruption; references herein to the Registration Statement shall include the new registration statement declared effective by the Commission.

(k) If requested by the Representatives, to prepare a final term sheet relating to the offering of the Shares, containing only information that describes the final terms of the Shares or the offering in a form consented to by the Representatives, and to file such final term sheet within the period required by Rule 433(d)(5)(ii) under the Securities Act following the date the final terms have been established for the offering of the Shares.

(l) To not take, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of Shares.

(m) To use its commercially reasonable efforts to list the Shares, subject to official notice of issuance, on the NYSE.

7. Expenses . Whether or not the transactions contemplated in this Agreement are consummated or this Agreement is terminated, the Company agrees to pay or cause to be paid all reasonable expenses incident to the performance of its obligations under this Agreement, including: (i) the fees, disbursements and expenses of the Company’s counsel and the Company’s accountants in connection with the registration and delivery of the Shares under the Securities Act and all other fees or expenses in connection with the preparation and filing of the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, the Prospectus, any free writing prospectus prepared by or on behalf of, used by, or referred to by the Company and amendments and supplements to any of the foregoing, including the filing fees payable to the Commission relating to the Shares (within the time required by Rule 456 (b)(1), if applicable), all printing costs associated therewith, and the mailing and delivering of copies thereof to the Underwriters and dealers, in the quantities hereinabove specified, (ii) all costs and expenses related to the transfer and delivery of the Shares to the Underwriters, including any transfer or other taxes payable thereon, (iii) the cost of printing or producing any Blue Sky or legal investment memorandum in connection with the offer and sale of the Shares under state securities laws and all expenses in connection with the qualification of the Shares for offer and sale under state securities laws as provided in Section 6(g) hereof, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection with such qualification and in connection with the Blue Sky or legal investment memorandum, (iv) all filing fees and the reasonable fees and disbursements of counsel to the Underwriters incurred in connection with the review and qualification of the offering of the Shares by the Financial Industry Regulatory Authority, (v) all costs and expenses incident to listing the Shares on the NYSE, (vi) the cost of, if any, printing certificates representing the Shares, (vii) the costs and charges of any transfer agent, registrar or depositary, (viii) the costs and expenses of the Company relating to investor presentations on any “road show” undertaken in connection with the marketing of the offering of the Shares, including, without limitation, expenses associated with the preparation or dissemination of any electronic road show, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants engaged in connection with the road show presentations with the prior approval of the Company, travel and

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lodging expenses of the representatives and officers of the Company and any such consultants, and the cost of any aircraft chartered in connection with the road show, (ix) the document production charges and expenses associated with printing this Agreement, (x) all expenses in connection with any offer and sale of the Shares outside of the United States, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection with offers and sales outside of the United States and (xi) all other costs and expenses incident to the performance of the obligations of the Company hereunder for which provision is not otherwise made in this Section. It is understood, however, that except as provided in this Section, Section 9 entitled “Indemnity and Contribution,” and the last paragraph of Section 11 below, the Underwriters will pay all of their costs and expenses, including fees and disbursements of their counsel, stock transfer taxes payable on resale of any of the Shares by them and any advertising expenses connected with any offers they may make.

8. Covenants of the Underwriters . Each Underwriter severally covenants with the Company not to take any action that would result in the Company being required to file with the Commission under Rule 433(d) a free writing prospectus prepared by or on behalf of such Underwriter that otherwise would not be required to be filed by the Company thereunder, but for the action of the Underwriter.

9. Indemnity and Contribution. (a) The Company agrees to indemnify and hold harmless each Underwriter, each person, if any, who controls any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act and each affiliate of any Underwriter within the meaning of Rule 405 under the Securities Act from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus as defined in Rule 433(h) under the Securities Act, any Company information that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or the Prospectus or any amendment or supplement thereto, or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, except insofar as such losses, claims, damages or liabilities are caused by any such untrue statement or omission or alleged untrue statement or omission based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through you expressly for use therein, it being understood and agreed that the only such information furnished by the Underwriters consists of the information described in clause (b) below.

(b) Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, the directors of the Company, the officers of the Company who sign the Registration Statement and each person, if any, who controls the Company within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus as defined in Rule 433(h) under the Securities

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Act, any Company information that the Company has filed, or is required to file, pursuant to Rule 433(d) of the Securities Act, or the Prospectus (as amended or supplemented if the Company shall have furnished any amendments or supplements thereto), or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, but only with reference to information relating to such Underwriter furnished to the Company in writing by such Underwriter through you expressly for use in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus or the Prospectus or any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information in the seventh, ninth and tenth paragraphs of the Underwriting section in the preliminary prospectus and the Prospectus.

(c) In case any proceeding (including any governmental investigation) shall be instituted involving any person in respect of which indemnity may be sought pursuant to Section 9(a) or 9(b), such person (the “ indemnified party ”) shall promptly notify the person against whom such indemnity may be sought (the “ indemnifying party ”) in writing and the indemnifying party, upon request of the indemnified party, shall retain counsel reasonably satisfactory to the indemnified party to represent the indemnified party and any others the indemnifying party may designate in such proceeding and shall pay the fees and disbursements of such counsel related to such proceeding. In any such proceeding, any indemnified party shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless (i) the indemnifying party and the indemnified party shall have mutually agreed to the retention of such counsel or (ii) the named parties to any such proceeding (including any impleaded parties) include both the indemnifying party and the indemnified party and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is understood that the indemnifying party shall not, in respect of the legal expenses of any indemnified party in connection with any proceeding or related proceedings in the same jurisdiction, be liable for (i) the fees and expenses of more than one separate firm (in addition to one local counsel in each jurisdiction) for all Underwriters and all persons, if any, who control any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act or who are affiliates of any Underwriter within the meaning of Rule 405 under the Securities Act and (ii) the fees and expenses of more than one separate firm (in addition to one local counsel in each jurisdiction) for the Company, its directors, its officers who sign the Registration Statement and each person, if any, who controls the Company within the meaning of either such Section, and that all such fees and expenses shall be reimbursed as they are incurred. In the case of any such separate firm for the Underwriters and such control persons and affiliates of any Underwriters, such firm shall be designated in writing by the Representatives. In the case of any such separate firm for the Company, and such directors, officers and control persons of the Company, such firm shall be designated in writing by the Company. The indemnifying party shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party from and against any loss or liability by reason of such settlement or judgment. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened proceeding in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party, unless (i) such settlement includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such proceeding and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party.

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(d) To the extent the indemnification provided for in Section 9(a) or 9(b) is unavailable to an indemnified party or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each indemnifying party under such paragraph, in lieu of indemnifying such indemnified party thereunder, shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other hand from the offering of the Shares or (ii) if the allocation provided by clause 9(d)(i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause 9(d)(i) above but also the relative fault of the Company on the one hand and of the Underwriters on the other hand in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other hand in connection with the offering of the Shares shall be deemed to be in the same respective proportions as the net proceeds from the offering of the Shares (before deducting expenses) received by the Company and the total underwriting discounts and commissions received by the Underwriters bear to the aggregate price at which the Shares are offered to the public, as set forth in the Prospectus. The relative fault of the Company on the one hand and the Underwriters on the other hand shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Underwriters’ respective obligations to contribute pursuant to this Section 9 are several in proportion to the respective number of Shares they have purchased hereunder, and not joint.

(e) The Company and the Underwriters agree that it would not be just or equitable if contribution pursuant to this Section 9 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in Section 9(d). The amount paid or payable by an indemnified party as a result of the losses, claims, damages and liabilities referred to in Section 9(d) shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 9, no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Shares underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The remedies provided for in this Section 9 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any indemnified party at law or in equity.

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(f) The indemnity and contribution provisions contained in this Section 9 and the representations, warranties and other statements of the Company contained in this Agreement shall remain operative and in full force and effect regardless of (i) any termination of this Agreement, (ii) any investigation made by or on behalf of any Underwriter, any person controlling any Underwriter or any affiliate of any Underwriter or by or on behalf of the Company, its officers or directors or any person controlling the Company and (iii) acceptance of and payment for any of the Shares.

10. Termination . The Underwriters may terminate this Agreement by notice given by you to the Company, if after the execution and delivery of this Agreement and prior to the Closing Date (i) trading generally shall have been suspended or materially limited on, or by, as the case may be, any of the NYSE or the NASDAQ Global Market, (ii) trading of any securities of the Company shall have been suspended on any exchange or in any over-the-counter market, (iii) a material disruption in securities settlement, payment or clearance services in the United States shall have occurred, (iv) any moratorium on commercial banking activities shall have been declared by Federal or New York State authorities or (v) there shall have occurred any outbreak or escalation of hostilities, or any change in financial markets or any calamity or crisis that, in your judgment, is material and adverse and which, singly or together with any other event specified in this clause (v), makes it, in your judgment, impracticable or inadvisable to proceed with the offer, sale or delivery of the Shares on the terms and in the manner contemplated in the Time of Sale Prospectus or the Prospectus.

11. Effectiveness; Defaulting Underwriters . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

If, on the Closing Date or an Option Closing Date, as the case may be, any one or more of the Underwriters shall fail or refuse to purchase Shares that it has or they have agreed to purchase hereunder on such date, and the aggregate number of Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase is not more than one-tenth of the aggregate number of the Shares to be purchased on such date, the other Underwriters shall be obligated severally in the proportions that the number of Firm Shares set forth opposite their respective names in Schedule I bears to the aggregate number of Firm Shares set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as you may specify, to purchase the Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date; provided that in no event shall the number of Shares that any Underwriter has agreed to purchase pursuant to this Agreement be increased pursuant to this Section 11 by an amount in excess of one-ninth of such number of Shares without the written consent of such Underwriter. If, on the Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Firm Shares which it or they have agreed to purchase hereunder on such date and the aggregate number of Firm Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Firm Shares to be purchased on such date, and arrangements satisfactory to you and the Company for the purchase of such Firm Shares are not made within 36 hours after such default, this Agreement shall terminate without liability on the part of any non-defaulting Underwriter or the Company. In any such case either you or the Company shall have the right to postpone the Closing Date, but in no event for longer than seven days, in order that the required changes, if any, in the Registration Statement, in the Time of Sale Prospectus, in the Prospectus or in any other documents or arrangements may be effected. If, on

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an Option Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Additional Shares and the aggregate number of Additional Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Additional Shares to be purchased on such Option Closing Date, the non-defaulting Underwriters shall have the option to (i) terminate their obligation hereunder to purchase the Additional Shares to be sold on such Option Closing Date or (ii) purchase not less than the number of Additional Shares that such non-defaulting Underwriters would have been obligated to purchase in the absence of such default. Any action taken under this paragraph shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement.

If this Agreement shall be terminated by the Underwriters, or any of them, because of any failure or refusal on the part of the Company to comply with the terms or to fulfill any of the conditions of this Agreement, or if for any reason the Company shall be unable to perform its obligations under this Agreement, the Company will reimburse the Underwriters or such Underwriters as have so terminated this Agreement with respect to themselves, severally, for all out-of-pocket expenses (including the fees and disbursements of their counsel) reasonably incurred by such Underwriters in connection with this Agreement or the offering contemplated hereunder.

12. Entire Agreement . (a) This Agreement, together with any contemporaneous written agreements and any prior written agreements (to the extent not superseded by this Agreement) that relate to the offering of the Shares, represents the entire agreement between the Company and the Underwriters with respect to the preparation of any preliminary prospectus, the Time of Sale Prospectus, the Prospectus, the conduct of the offering, and the purchase and sale of the Shares.

(b) The Company acknowledges that in connection with the offering of the Shares: (i) the Underwriters have acted at arm’s length, are not agents of, and owe no fiduciary duties to, the Company or any other person, (ii) the Underwriters owe the Company only those duties and obligations set forth in this Agreement and prior written agreements (to the extent not superseded by this Agreement), if any, and (iii) the Underwriters may have interests that differ from those of the Company. The Company waives to the full extent permitted by applicable law any claims it may have against the Underwriters arising from an alleged breach of fiduciary duty in connection with the offering of the Shares.

13. Counterparts . This Agreement may be signed in two or more counterparts, each of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument.

14. Applicable Law . This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the internal laws of the State of New York.

15. Headings . The headings of the sections of this Agreement have been inserted for convenience of reference only and shall not be deemed a part of this Agreement.

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16. Compliance with USA Patriot Act . In accordance with the requirements of the USA PATRIOT Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), each of the Underwriters is required to obtain, verify and record information that identifies its clients, including the Company, which information may include the name and address of its clients, as well as other information that will allow each of the Underwriters to properly identify its clients.

17. Notices . All communications hereunder shall be in writing and effective only upon receipt and if to the Underwriters shall be delivered, mailed or sent to you at the address set forth in Schedule II hereto; and if to the Company shall be delivered, mailed or sent to the address set forth in Schedule II hereto.

[signature pages follow]

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[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]

Exhibit 1.2

Execution Version

1,500,000 Shares

CROWN CASTLE INTERNATIONAL CORP.

6.875% Mandatory Convertible Preferred Stock, Series A

PAR VALUE $0.01 PER SHARE

UNDERWRITING AGREEMENT

July 20, 2017

July 20, 2017

Morgan Stanley & Co. LLC

1585 Broadway

New York, NY 10036

Merrill Lynch, Pierce, Fenner & Smith

Incorporated

One Bryant Park

New York, NY 10036

J.P. Morgan Securities LLC

383 Madison Avenue

New York, NY 10179

as Representatives for the Underwriters

named in Schedule I hereto

Ladies and Gentlemen:

Crown Castle International Corp., a Delaware corporation (the “ Company ”), proposes to issue and sell to you, the several underwriters named in Schedule I hereto (the “ Underwriters ”), for whom you are acting as representatives (“ Representatives ”), 1,500,000 shares of its 6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share (the “ Firm Shares ”). The Company also proposes to issue and sell to the several Underwriters not more than an additional 150,000 shares of its 6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share (the “ Additional Shares ”), if and to the extent that you, as Representatives of the offering, shall have determined to exercise, on behalf of the Underwriters, the right to purchase such shares granted to the Underwriters in Section 2 hereof. The Firm Shares and the Additional Shares are hereinafter collectively referred to as the “ Shares .” The 6.875% Mandatory Convertible Preferred Stock, Series A, par value $0.01 per share, of the Company are hereinafter referred to as the “ Preferred Shares .” The Preferred Shares will be convertible into a variable number of shares of common stock, par value $0.01 per share, of the Company. Such shares of common stock into which the Shares are convertible are hereinafter referred to as the “ Conversion Shares ” and the shares of common stock, par value $0.01 per share, generally, of the Company are hereinafter referred to as “ Common Stock .”

The terms of the Preferred Shares will be set forth in a Certificate of Designations (the “ Certificate of Designations ”) to be filed by the Company with the Secretary of State of the State of Delaware.

The Company has filed with the Securities and Exchange Commission (the “ Commission ”) a registration statement, including a prospectus, on Form S-3 (No. 333-203074), relating to securities (the “ Shelf Securities ”), including the Shares, to be issued from time to time thereunder by the Company. The registration statement, as amended to the date of this Agreement, including the information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A or Rule 430B under the Securities Act of 1933, as amended (the “ Securities Act ”), is hereinafter referred to as the “ Registration Statement ,” and the related prospectus covering the Shelf Securities dated March 27, 2015, in the form first used to confirm sales of the Shares (or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Basic Prospectus .” The Basic Prospectus, as supplemented by the prospectus supplement specifically relating to the Shares in the form first used to confirm sales of the Shares (or in the form first made available to the Underwriters by the Company to meet requests of purchasers pursuant to Rule 173 under the Securities Act) is hereinafter referred to as the “ Prospectus ,” and the term “ preliminary prospectus ” means any preliminary form of the Prospectus. For purposes of this Agreement, “ free writing prospectus ” has the meaning set forth in Rule 405 under the Securities Act, “ Time of Sale Prospectus ” means the documents set forth opposite the caption “Time of Sale Prospectus” in Schedule II hereto and the information identified on Schedule II-A hereto, and “ road show ” means a “bona fide electronic road show” as defined in Rule 433(h)(5) under the Securities Act. As used herein, the terms “Registration Statement,” “Basic Prospectus,” “preliminary prospectus,” “Time of Sale Prospectus” and “Prospectus” shall include the documents, if any, incorporated by reference therein. The terms “ supplement ,” “ amendment ,” and “ amend ” as used herein with respect to the Registration Statement, the Basic Prospectus, the Time of Sale Prospectus, any preliminary prospectus, any free writing prospectus or the Prospectus shall include all documents subsequently filed by the Company with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), that are deemed to be incorporated by reference therein.

1. Representations and Warranties of the Company . The Company represents and warrants to and agrees with each of the Underwriters that:

(a) The Registration Statement has become effective; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company, threatened by the Commission. The Registration Statement is an automatic shelf registration statement as defined in Rule 405 under the Securities Act, and the Company is a well-known seasoned issuer (as defined in Rule 405 under the Securities Act) eligible to use the Registration Statement as an automatic shelf registration statement, and the Company has not received notice that the Commission objects to the use of the Registration Statement as an automatic shelf registration statement.

(b) (i) Each document, if any, filed or to be filed pursuant to the Exchange Act and incorporated by reference in the Time of Sale Prospectus or the Prospectus complied or will comply when so filed in all material respects with the Exchange Act and the applicable rules and regulations of the Commission thereunder, (ii) each part of the Registration Statement, when such part became effective, did not contain, and each such part, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iii) the

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Registration Statement does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (iv) the Registration Statement, as of the date hereof, complies, and the Prospectus, as of its date, will comply, and the Registration Statement and the Prospectus, as amended or supplemented, if applicable, will comply, as of the Closing Date (as defined in Section 4), in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder, (v) the Time of Sale Prospectus does not, and at the time of each sale of the Shares in connection with the offering when the Prospectus is not yet available to prospective purchasers and at the Closing Date, the Time of Sale Prospectus, as then amended or supplemented by the Company, if applicable, will not, contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, (vi) each road show, if any, when considered together with the Time of Sale Prospectus, does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading and (vii) the Prospectus, as of its date, will not contain and, as amended or supplemented, if applicable, will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, except that the representations and warranties set forth in this paragraph do not apply to statements or omissions in the Registration Statement, the Time of Sale Prospectus or the Prospectus based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein, which is set forth in Section 9(b) hereof.

(c) The Company is not an “ineligible issuer” in connection with the offering pursuant to Rules 164, 405 and 433 under the Securities Act. Any free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Each free writing prospectus that the Company has filed, or is required to file, in connection with the offering of Shares pursuant to Rule 433(d) under the Securities Act or that was prepared by or on behalf of or used or referred to by the Company complies, or will comply, in all material respects with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Except for the free writing prospectuses, if any, identified in Schedule II hereto forming part of the Time of Sale Prospectus, and road shows, if any, each furnished to you before first use, the Company has not prepared, used or referred to, and will not, without your prior consent, prepare, use or refer to, any free writing prospectus.

(d) Neither the Company nor any of its subsidiaries has sustained, since the date of the latest audited financial statements incorporated by reference into the Registration Statement, the Time of Sale Prospectus or the Prospectus, any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the Time of Sale Prospectus and the Prospectus or as would not reasonably be expected, in the aggregate, to result in a Material Adverse Effect (as defined below); and, since the respective dates as of which information is given in the Time of Sale Prospectus and the Prospectus, there has not been any change in the capital stock or long-term debt of the Company

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or any of its subsidiaries or any material adverse change, or any development involving a prospective material adverse change, except such as are described in the Time of Sale Prospectus and the Prospectus or such as would not be reasonably expected, in the aggregate, to result in a material adverse effect on the condition (financial or other), business, properties or results of operations of the Company and the Material Subsidiaries (as defined below), taken as a whole (a “ Material Adverse Effect ”). As of the date hereof, each subsidiary of the Company that constitutes a “ significant subsidiary ,” as such term is defined in Rule 405 of the rules and regulations under the Securities Act, is a “ Material Subsidiary ” and, collectively, comprise the “ Material Subsidiaries .”

(e) (i) The Company and each of its subsidiaries have (1) good and marketable fee or leasehold title, as applicable, to all real property owned or leased by them and (2) good and marketable title to all personal property owned by them; and (ii) any other personal property leased or held by the Company or any of its subsidiaries pursuant to any licenses, easements, management agreements, other contracts or occupancy agreements or otherwise is leased or held under valid, subsisting and enforceable agreements, in each case free and clear of all liens, encumbrances and defects except such as are described in the Time of Sale Prospectus and the Prospectus or would not reasonably be expected, in the aggregate, to have a Material Adverse Effect.

(f) The Company is a corporation duly incorporated and validly existing and in good standing under the laws of the State of Delaware with all requisite corporate power and authority to own, lease and operate its properties and to conduct its business as described in the Time of Sale Prospectus and the Prospectus, and is duly registered and qualified to conduct its business and is in good standing in each jurisdiction or place where the nature of its properties or the conduct of its business requires such registration or qualification, except where the failure so to register or qualify or to be in good standing would not have a Material Adverse Effect; and each Material Subsidiary of the Company has been duly incorporated or formed, as the case may be, and is validly existing as a corporation, limited partnership, limited liability company or other legal entity in good standing or the equivalent under the laws of its jurisdiction of incorporation or formation, as the case may be.

(g) The Company has an authorized capitalization as set forth in the Time of Sale Prospectus and the Prospectus, and all the shares of Common Stock outstanding prior to the issuance of the Shares have been duly authorized and are validly issued, fully paid and non-assessable, and conform to the description of the Common Stock contained in the Time of Sale Prospectus and the Prospectus; and all of the issued shares of capital stock of each Material Subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims, except as set forth in the Time of Sale Prospectus and the Prospectus.

(h) Neither the Company nor any of its subsidiaries, nor, to the knowledge of the Company, any of their respective affiliates, has taken any action which is designed to or which has constituted or which might have been reasonably expected to cause or result in stabilization or manipulation of the price of any security of the Company in connection with the offering of the Shares.

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(i) No “nationally recognized statistical rating organization” (as such term is defined for purposes of Section 3(a)(62) under the Exchange Act) has imposed any condition (financial or otherwise) on the Company or any of its subsidiaries relating to any rating assigned to the Company or any such subsidiary or to any securities of the Company or any such subsidiary.

(j) The Certificate of Designations, the proposed form of which has been furnished to you, has been duly authorized by the Company and will have been duly executed and delivered by the Company and duly filed with the Secretary of State of the State of Delaware on or prior to the Closing Date. The Certificate of Designations sets forth the rights, powers, preferences and designations of the Shares.

(k) The Shares have been duly authorized and, when issued and delivered in accordance with the terms of this Agreement, will be validly issued, fully paid and non-assessable and will have the rights, powers, preferences and designations as set forth in the Certificate of Designations, and the issuance of such Shares will not be subject to any preemptive or similar rights.

(l) The form of certificate used to evidence the Shares complies in all material respects with all applicable requirements of the law of the State of Delaware, the New York Stock Exchange (the “ NYSE ”) and the Company’s certificate of incorporation and by-laws, and has been duly authorized and approved by the board of directors of the Company.

(m) The Shares will be convertible into the Conversion Shares in accordance with the terms of the Preferred Shares set forth in the Certificate of Designations; a number of Conversion Shares (the “ Maximum Number of Conversion Shares ”) equal to the product of (A) the sum of (i) a number of shares of Common Stock equal to the maximum conversion rate for the Preferred Shares and (ii) to the extent so elected by the Company in connection with any such conversion, the number of shares of Common Stock deliverable by the Company upon conversion in respect of dividends payable upon conversion of the Shares (whether or not declared) (assuming the Company elects to issue and deliver, in respect of accumulated and unpaid dividends (whether or not declared), the maximum number of shares of Common Stock in connection with any such conversion), multiplied by (B) the aggregate number of Shares, in each case in accordance with the terms of the Certificate of Designations, has been and will be duly authorized and reserved for issuance by the Company and such Conversion Shares, when issued upon such conversion or delivery (as the case may be) in accordance with the terms of the Preferred Shares set forth in the Certificate of Designations, will be validly issued, fully paid and non-assessable, will conform in all material respects to the descriptions thereof in the Time of Sale Prospectus and the Prospectus and will not be subject to any preemptive or similar rights.

(n) The execution and delivery by the Company of, and the performance by the Company of its obligations under, this Agreement and the Certificate of Designations, including the issuance and sale of the Shares and the issuance of a number of Conversion Shares equal to the Maximum Number of Conversion Shares issuable by the Company in accordance with the terms of the Certificate of Designations, will not conflict with, or result in a breach or violation of, any of the terms or provisions of or, with the giving of notice or the lapse of time or both, constitute a default under (A) any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which

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the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (B) the provisions of the charter, by-laws or other constitutive documents of the Company or any of its subsidiaries or (C) any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets except in the cases of clause (A) or (C), such breaches, violations or defaults that in the aggregate would not have a Material Adverse Effect; and no consent, approval, authorization, order, registration or qualification of or with any such court or governmental agency or body is required for the performance by the Company of its obligations under this Agreement and the Certificate of Designations, including the issuance and sale of the Shares and the issuance of a number of Conversion Shares equal to the Maximum Number of Conversion Shares issuable by the Company in accordance with the terms of the Certificate of Designations, except where the failure to obtain or make such consents, approvals, authorizations, registrations or qualifications would not, individually or in the aggregate, have a Material Adverse Effect.

(o) (A) Neither the Company nor any of its Material Subsidiaries is in violation of its charter, by-laws or other constitutive documents, (B) neither the Company nor any of its subsidiaries is in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any material indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which it is a party or by which it is bound or to which any of its properties or assets is subject or (C) neither the Company nor any of its subsidiaries is in violation of any law, ordinance, governmental rule, regulation or court decree to which it or its property or assets may be subject or has failed to obtain any material license, permit, certificate, franchise or other governmental authorization or permit necessary to the ownership of its property or to the conduct of its business, except for, in the cases of clause (B) or (C), such defaults, violations or failures to obtain that in the aggregate would not have a Material Adverse Effect.

(p) The statements contained in (A) the Time of Sale Prospectus and the Prospectus under the captions “Description of Capital Stock,” “Description of Mandatory Convertible Preferred Stock” and “Material United States Federal Income Tax Considerations” and (B) the Prospectus under the caption “Underwriting,” insofar as they are descriptions of contracts, agreements or other legal documents, or refer to statements of law or legal conclusions, are accurate in all material respects and present fairly the information purported to be described therein.

(q) Other than as set forth in the Time of Sale Prospectus and the Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

(r) Each preliminary prospectus filed as part of the Registration Statement as originally filed or as part of any amendment thereto, or filed pursuant to Rule 424 under the Securities Act, complied when so filed in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder.

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(s) The Company is not, and after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Prospectus will not be, required to register as an “investment company” as such term is defined in the Investment Company Act of 1940, as amended.

(t) There has been no storage, disposal, generation, manufacture, refinement, transportation, handling or treatment of toxic wastes, medical wastes, hazardous wastes or hazardous substances by the Company or any of its subsidiaries (or, to the knowledge of the Company, any of their predecessors in interest) at, upon or from any of the property now or previously owned or leased by the Company or any of its subsidiaries in violation of any applicable law, ordinance, rule, regulation, order, judgment, decree or permit or which would require remedial action under any applicable law, ordinance, rule, regulation, order, judgment, decree or permit, except for any violation or remedial action which would not have, or could not be reasonably likely to have, singularly or in the aggregate, a Material Adverse Effect; there has been no material spill, discharge, leak, emission, injection, escape, dumping or release of any kind onto such property or into the environment surrounding such property of any toxic wastes, medical wastes, solid wastes, hazardous wastes or hazardous substances due to or caused by the Company or any of its subsidiaries or with respect to which the Company or any of its subsidiaries has knowledge, except for any such spill, discharge, leak, emission, injection, escape, dumping or release which would not have or would not be reasonably likely to have, singularly or in the aggregate, a Material Adverse Effect; and the terms “hazardous wastes,” “toxic wastes,” “hazardous substances” and “medical wastes” shall have the meanings specified in any applicable local, state, federal and foreign laws or regulations with respect to environmental protection.

(u) Except as set forth in the Registration Statement, the Time of Sale Prospectus and the Prospectus, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Securities Act with respect to any securities of the Company or to require the Company to include such securities with the Shares registered pursuant to the Registration Statement.

(v) PricewaterhouseCoopers LLP, who has certified certain financial statements of the Company and its subsidiaries, are independent public accountants with respect to the Company as required by the Securities Act and the rules and regulations of the Commission thereunder and the rules and regulations of the Public Company Accounting Oversight Board.

(w) To the knowledge of the Company, Deloitte & Touche LLP, who has certified the consolidated financial statements of LTS Group Holdings LLC (“ Target ”) as of and for the year ended December 31, 2016 incorporated by reference in the Time of Sale Prospectus and the Prospectus, were independent public accountants with respect to Target as defined by the Securities Act and the rules and regulations of the Commission thereunder.

(x) To the knowledge of the Company, the Consolidated Statement of Income of the Target fairly presents the revenues and certain expenses relating to the Target for the respective periods indicated, in each case in accordance with generally accepted accounting principles consistently applied throughout such periods.

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(y) The Company has all requisite corporate power and authority to execute and deliver this Agreement and to otherwise perform its obligations under this Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(z) The Company’s consolidated historical financial statements, together with the related notes thereto, incorporated by reference into the Time of Sale Prospectus and the Prospectus, comply as to form in all material respects with the applicable requirements of Regulation S-X under the Securities Act. Such consolidated historical financial statements fairly present the financial position of the Company at the respective dates indicated and the results of operations and cash flows for the respective periods indicated, in each case in accordance with generally accepted accounting principles consistently applied throughout such periods. The other financial and statistical information and data incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus (other than the estimated financial and statistical information and data related to the Lightower Acquisition (as defined in the Time of Sale Prospectus and Prospectus)) is, in all material respects, fairly presented and prepared on a basis consistent with the financial statements and the books and records of the Company. The interactive data in eXtensible Business Reporting Language incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus fairly presents the information called for and is prepared in accordance with the Commission’s rules and guidance applicable thereto, in each case, in all material respects. The estimated financial and statistical information and data relating to the Lightower Acquisition included in the Time of Sale Prospectus and the Prospectus were prepared in good faith, are reasonable in the good faith judgment of the Company and are based on or derived from sources that the Company believes to be reliable for the purpose of preparing such estimates.

(aa) The Company and each of the Material Subsidiaries has such permits, licenses, franchises, registrations and other approvals or authorizations of any governmental or regulatory authority (“ Permits ”), including, without limitation, any permits required by the Federal Communications Commission (“ FCC ”) or the Federal Aviation Administration, as are necessary under applicable law to own their respective properties and to conduct their respective businesses in the manner described in the Time of Sale Prospectus and the Prospectus, except to the extent that the failure to have such Permits would not have a Material Adverse Effect. The Company and the Material Subsidiaries have fulfilled and performed, in all material respects, all of their respective obligations with respect to the Permits, and no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other impairment of the rights of, or imposition of a penalty on, the holder of any such Permit, subject in each case to such qualification as may be set forth in the Time of Sale Prospectus and the Prospectus and except to the extent that any such revocation, termination, impairment or penalty would not have a Material Adverse Effect. Except as described in the Time of Sale Prospectus and the Prospectus, none of the Permits contains any restriction that has not previously been satisfied and that is materially burdensome to the Company or any of the Material Subsidiaries.

(bb) For each existing tower of the Company not yet registered with the FCC where registration will be required, the FCC’s grant of an application for registration of such tower will not have a significant environmental effect as defined under Section 1.1307(a) or (b) of the FCC’s rules.

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(cc) The consummation of the transactions contemplated by this Agreement shall not cause any third party to have any rights of first refusal with respect to the acquisition of towers of the Company or any of its subsidiaries under any agreement filed as an exhibit to any document incorporated by reference in the Prospectus (the “ Material Agreements ”) that has not already been described in the Time of Sale Prospectus and the Prospectus as to which the Company and any of the Material Subsidiaries or any of their property or assets may be subject.

(dd) The Company and each of the Material Subsidiaries owns or possesses all patents, trademarks, trademark registrations, service marks, service mark registrations, trade names, copyrights, licenses, inventions, trade secrets and rights described in the Time of Sale Prospectus and the Prospectus as being owned by any of them or necessary for the conduct of their respective businesses, and neither the Company nor any of the Material Subsidiaries is aware of any claim to the contrary or any challenge by any other person to the rights of the Company or any of the Material Subsidiaries with respect to such rights that, if determined adversely to the Company or any such Material Subsidiary, would individually or in the aggregate have a Material Adverse Effect.

(ee) Neither the Company nor any of its subsidiaries is involved in any strike, job action or labor dispute with any group of employees, and, to the knowledge of the Company and its subsidiaries, no such action or dispute is threatened.

(ff) The Company and each of its subsidiaries are in compliance in all material respects with all presently applicable provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder (“ ERISA ”); no “reportable event” (as defined in ERISA) has occurred with respect to any “pension plan” (as defined in ERISA) for which the Company would have any liability; the Company has not incurred and does not expect to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any “pension plan” or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the “ Code ”); and each “pension plan” for which the Company would have any liability that is intended to be qualified under Section 401(a) of the Code is so qualified in all material respects and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification.

(gg) The Company and each of its subsidiaries have filed all federal, state and local income and franchise tax returns required to be filed through the date hereof and have paid all taxes required to be paid to the extent due and payable, except to the extent any such taxes are currently being contested in good faith, and no tax deficiency has been determined adversely to the Company or any of its subsidiaries nor does the Company or any of its subsidiaries have any knowledge of any tax deficiency, except where such failure to file such tax return or pay such tax deficiency (if determined adversely to the Company or any of its subsidiaries) would not have a Material Adverse Effect.

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(hh) The Company operates in conformity with the requirements for qualification and taxation as a “real estate investment trust” (a “ REIT ”) under Sections 856 through 860 of the Code; and the method of operation for the Company and its subsidiaries as described in the Prospectus will enable the Company to meet the requirements for qualification and taxation as a REIT under the Code.

(ii) The Company (i) makes and keeps accurate books and records and (ii) maintains a system of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) to provide reasonable assurance that (A) transactions are executed in accordance with management’s authorization, (B) transactions are recorded as necessary to permit preparation of its financial statements in conformity with generally accepted accounting principles and to maintain accountability for assets, (C) access to its financial assets is permitted only in accordance with management’s general or specific authorization, (D) the reported accountability for its assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences and (E) the interactive data in eXtensible Business Reporting Language incorporated or included in the Registration Statement, the Time of Sale Prospectus and the Prospectus is, in all material respects, prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(jj) The Company and each of the Material Subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as is adequate for the conduct of its businesses and the value of its properties and as is customary for companies engaged in similar businesses in similar industries.

(kk) The Company has established and maintains disclosure controls and procedures (as such term is defined in Rule 13a-14 and 15d-14 under the Exchange Act); such disclosure controls and procedures are designed to ensure that material information relating to the Company, including its consolidated subsidiaries, is made known to the Company’s Chief Executive Officer and its Chief Financial Officer by others within those entities, and such disclosure controls and procedures are effective to perform the functions for which they were established; the Company’s auditors and the Audit Committee of the Board of Directors have been advised of: (A) any significant deficiencies in the design or operation of internal controls which could adversely affect the Company’s ability to record, process, summarize, and report financial data; and (B) any fraud, whether or not material, that involves management or other employees who have a role in the Company’s internal controls; any material weaknesses in internal controls have been identified for the Company’s auditors; and since the date of the most recent evaluation of such disclosure controls and procedures, there have been no significant changes in internal controls or in other factors that could significantly affect internal controls, including any corrective actions with regard to significant deficiencies and material weaknesses.

(ll) There is and has been no failure on the part of the Company and any of the Company’s directors or officers, in their capacities as such, to comply with the provisions of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith.

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(mm) Neither the Company or any of its subsidiaries, nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate or other person acting on behalf of the Company or any of its subsidiaries, has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “ FCPA ”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA; (iii) violated or is in violation of any provision of the FCPA, or any applicable law or regulation implementing the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, or committed an offence under the Bribery Act 2010 of the United Kingdom, or any other applicable anti-bribery or anti-corruption law; or (iv) made, offered, agreed, requested or taken an act in furtherance of any unlawful bribe or provided an unlawful benefit, including, without limitation, any rebate, payoff, influence payment, kickback or other unlawful payment or benefit. The Company and its subsidiaries have instituted, maintain and enforce, and reasonably expect to continue to maintain and enforce, policies and procedures designed to ensure compliance with applicable anti-bribery and anti-corruption laws.

(nn) The operations of the Company and its subsidiaries are and have been conducted at all times in material compliance with all applicable financial recordkeeping and reporting requirements, including those of the Currency and Foreign Transactions Reporting Act of 1970, as amended by Title III of the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001 (USA PATRIOT Act), and the applicable money laundering statutes of all jurisdictions where the Company or any of its subsidiaries conduct business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “ Anti-Money Laundering Laws ”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(oo) Neither the Company or any of its subsidiaries, nor, to the knowledge of the Company, any director, officer, employee, agent, affiliate or other person acting on behalf of the Company or any of its subsidiaries, is currently the subject or the target of any sanctions administered or enforced by the U.S. government (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury or the U.S. Department of State and including, without limitation, the designation as a “specially designated national” or “blocked person”), the United Nations Security Council, the European Union, Her Majesty’s Treasury, or other relevant sanctions authority (collectively, “ Sanctions ”), nor is any of the Company or any of its subsidiaries located, organized or resident in a country or territory that is the subject or target of Sanctions, including, without limitation, Crimea, Cuba, Iran, North Korea, Sudan and Syria (each, a “ Sanctioned Country ”); and the Company will not directly or indirectly use the proceeds of the offering of the Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity (i) to fund or facilitate any activities of or conduct business with any person that, at the time of such funding or facilitation, is the subject or target of Sanctions or (ii) to fund or facilitate any activities of or conduct business in any Sanctioned Country.

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2. Agreements to Sell and Purchase . The Company hereby agrees to sell to the several Underwriters, and each Underwriter, upon the basis of the representations and warranties herein contained, but subject to the conditions hereinafter stated, agrees, severally and not jointly, to purchase from the Company at $975.00 a share (the “ Purchase Price ”) the number of Firm Shares set forth in Schedule I hereto opposite the name of such Underwriter.

On the basis of the representations and warranties contained in this Agreement, and subject to its terms and conditions, the Company agrees to sell to the Underwriters the Additional Shares, and the Underwriters shall have the right to purchase, severally and not jointly, up to 150,000 Additional Shares solely to cover overallotments, if any, at the Purchase Price, provided, however, that the amount per share paid by the Underwriters for any Additional Shares shall be reduced by an amount per share equal to any dividends declared by the Company and payable on the Firm Shares but not payable on such Additional Shares. The Representatives may exercise this right on behalf of the Underwriters in whole or from time to time in part by giving written notice not later than 30 days after the date of this Agreement. Any exercise notice shall specify the number of Additional Shares to be purchased by the Underwriters and the date on which such shares are to be purchased. Each purchase date must be at least one business day after the written notice is given and may not be earlier than the closing date for the Firm Shares nor later than ten business days after the date of such notice. Additional Shares may be purchased as provided in Section 4 hereof. On each day, if any, that Additional Shares are to be purchased (an “ Option Closing Date ”), each Underwriter agrees, severally and not jointly, to purchase the number of Additional Shares (subject to such adjustments to eliminate fractional shares as you may determine) that bears the same proportion to the total number of Additional Shares to be purchased on such Option Closing Date as the number of Firm Shares set forth in Schedule I hereto opposite the name of such Underwriter bears to the total number of Firm Shares.

The Company also covenants with each Underwriter that, without the prior written consent of the Representatives on behalf of the Underwriters, it will not, during the period ending 60 days after the date of the Prospectus, (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any Preferred Shares or Common Stock or any securities convertible into or exercisable or exchangeable for Preferred Shares or Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Preferred Shares or Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Preferred Shares or Common Stock or such other securities, in cash or otherwise or (3) file any registration statement with the Commission relating to the offering of any shares of Preferred Shares or Common Stock or any securities convertible into or exercisable or exchangeable for Preferred Shares or Common Stock.

The restrictions contained in the preceding paragraph shall not apply to (a) the Preferred Shares to be sold hereunder (including the conversion thereof), shares of Common Stock issued in connection with the payment of dividends with respect thereto or the Conversion Shares issuable upon conversion thereof, (b) the issuance by the Company of Common Stock upon the

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exercise of an option or warrant or the conversion of a security outstanding on the date hereof of which the Underwriters have been advised in writing or which has been disclosed in the Time of Sale Prospectus, (c) the issuance by the Company or any of its subsidiaries of equity awards pursuant to employee benefit plans described in the Time of Sale Prospectus (including Common Stock issued under any such equity awards upon vesting), (d) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of Common Stock, provided that (i) such plan does not provide for the transfer of Common Stock during the 60-day restricted period and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is required of or voluntarily made by or on behalf of the Company regarding the establishment of such plan, such announcement or filing shall include a statement to the effect that no transfer of Common Stock may be made under such plan during the 60-day restricted period, (e) the filing of one or more registration statements on Form S-8 with the Commission with respect to the Common Stock issued or issuable under any employee benefit plan described in the Time of Sale Prospectus, (f) the issuance by the Company of up to 36,500,000 shares of Common Stock pursuant to that certain Underwriting Agreement, dated as of the date hereof, by and among the Company and the Representatives, as representatives of the several underwriters named in Schedule I thereto (the “ Common Stock Offering ”), or (g) the issuance of securities in connection with joint ventures, commercial relationships or other strategic transactions; provided that, in the case of this clause (g), (i) the aggregate number of shares of the Common Stock to be issued in all such transactions referenced in this clause (g) does not exceed 10% of the outstanding Common Stock immediately following the Common Stock Offering and (ii) the recipient thereof enters into a lock-up letter substantially in the form of Exhibit A hereto with respect to the remaining 60-day restricted period.

3. Public Offering . The Company is advised by you that the Underwriters propose to make a public offering of their respective portions of the Shares as soon after this Agreement has become effective as in your judgment is advisable. The Company is further advised by you that the Shares are to be offered to the public upon the terms set forth in the Prospectus.

4. Payment and Delivery. Payment for the Firm Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Firm Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on July 26, 2017, or at such other time on the same or such other date, not later than August 2, 2017, as shall be designated in writing by you. The time and date of such payment are hereinafter referred to as the “ Closing Date .”

Payment for any Additional Shares shall be made to the Company in Federal or other funds immediately available in New York City against delivery of such Additional Shares for the respective accounts of the several Underwriters at 10:00 a.m., New York City time, on the date specified in the corresponding notice described in Section 2 or at such other time on the same or on such other date, in any event not later than August 25, 2017, as shall be designated in writing by the Representatives.

The Firm Shares and Additional Shares shall be registered in such names and in such denominations as you shall request in writing not later than one full business day prior to the Closing Date or the applicable Option Closing Date, as the case may be. The Firm Shares and Additional Shares shall be delivered to you on the Closing Date or an Option Closing Date, as the case may be, for the respective accounts of the several Underwriters, with any transfer taxes payable in connection with the transfer of the Shares to the Underwriters duly paid, against payment of the Purchase Price therefor.

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5. Conditions . (I) The obligations of the Company to sell the Shares to the Underwriters and the several obligations of the Underwriters to purchase and pay for the Shares on the Closing Date are subject to the condition that the Prospectus, as amended or supplemented, in relation to the Shares, shall have been filed with the Commission pursuant to Rule 424(b) within the applicable time period described for such filing by the rules and regulations under the Securities Act, and as of the Closing Date and each Option Closing Date, no stop order suspending the effectiveness of the Registration Statement shall be in effect or shall be pending or, to the knowledge of the Company, threatened by the Commission; and no notice objecting to its use pursuant to Rule 401(g)(2) shall have been issued and no proceeding for such purpose or pursuant to Section 8A of the Securities Act shall have been instituted or threatened.

The several obligations of the Underwriters are subject to the following further conditions:

(a) Subsequent to the execution and delivery of this Agreement and prior to the Closing Date:

(i) there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded any of the securities of the Company or any of its subsidiaries by any “nationally recognized statistical rating organization,” as such term is defined for purposes of Section 3(a)(62) under the Exchange Act; and

(ii) there shall not have occurred any change, or any development involving a prospective change, in the condition, financial or otherwise, or in the earnings, business or operations of the Company and its subsidiaries, taken as a whole, from that set forth in the Time of Sale Prospectus as of the date of this Agreement that, in the Underwriters’ judgment, is material and adverse and that makes it, in the Underwriters’ judgment, impracticable to market the Shares on the terms and in the manner contemplated in the Time of Sale Prospectus.

(b) The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by an executive officer of the Company, to the effect set forth in Section 5(I)(a)(i) above and to the effect that the representations and warranties of the Company contained in this Agreement are true and correct as of the Closing Date and that the Company has complied with all of the agreements and satisfied all of the conditions on its part to be performed or satisfied hereunder on or before the Closing Date.

Any officer signing and delivering such certificate may rely upon the best of his or her knowledge as to proceedings threatened.

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(c) The Underwriters shall have received on the Closing Date an opinion, including an opinion with regard to the Company’s qualification and taxation as a REIT, and a negative assurance letter of Cravath, Swaine & Moore LLP, outside counsel for the Company, each dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(d) The Underwriters shall have received on the Closing Date an opinion of Skadden, Arps, Slate, Meagher & Flom LLP, tax counsel for the Company, with regard to the Company’s qualification and taxation as a REIT, dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(e) The Underwriters shall have received on the Closing Date an opinion of the General Counsel or Associate General Counsel to the Company, dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(f) The Underwriters shall have received on the Closing Date an opinion and a negative assurance letter of Skadden, Arps, Slate, Meagher & Flom LLP, counsel for the Underwriters, each dated the Closing Date, in form and substance reasonably acceptable to the Underwriters.

(g) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from PricewaterhouseCoopers LLP, independent public accountants, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in the Registration Statement, the Time of Sale Prospectus and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than three business days prior to the Closing Date.

(h) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from Deloitte & Touche LLP, independent public accountants to Target, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the consolidated financial statements of Target as of and for the year ended December 31, 2016 contained in the Time of Sale Prospectus and the Prospectus; provided that the letter delivered on the Closing Date shall use a “cut-off date” not earlier than three business days prior to the Closing Date.

(i) The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and the officers and directors of the Company listed in Exhibit B hereto relating to sales and certain other dispositions of shares of Preferred Shares and Common Stock or certain other securities, delivered to you on or before the date hereof, shall be in full force and effect on the Closing Date.

(j) The Underwriters shall have received, on each of the date hereof and the Closing Date, a letter dated the date hereof or the Closing Date, as the case may be, in form and substance satisfactory to the Underwriters, from Daniel K. Schlanger, Senior Vice President and Chief Financial Officer of the Company, substantially in the form of Exhibit C hereto.

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(k) On or prior to the Closing Date, the Certificate of Designations shall have been filed with the Secretary of State of the State of Delaware and become effective and the Company shall have delivered a copy thereof, certified by the Secretary of State of the State of Delaware, to the Representatives.

(l) The Company shall have filed the requisite listing application with the NYSE for the listing of the Shares and a number of Conversion Shares equal to the Maximum Number of Conversion Shares on the NYSE.

(m) On or prior to the Closing Date, the Company shall have furnished to the Representatives such further certificates and documents as the Representatives may reasonably request.

(n) The representations and warranties of the Company contained herein shall be true and correct on and as of the Closing Date.

(II) The several obligations of the Underwriters to purchase Additional Shares hereunder are subject to the delivery to you on the applicable Option Closing Date of the following:

(a) a certificate, dated the Option Closing Date and signed by an executive officer of the Company, confirming that the certificate delivered on the Closing Date pursuant to Section 5(I)(b) hereof remains true and correct as of such Option Closing Date;

(b) an opinion, including an opinion with regard to the Company’s qualification and taxation as a REIT, and a negative assurance letter of Cravath, Swaine & Moore LLP, outside counsel for the Company, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(c) hereof;

(c) an opinion of Skadden, Arps, Slate, Meagher & Flom LLP, tax counsel for the Company, with regard to the Company’s qualification and taxation as a REIT, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(d) hereof;

(d) an opinion of the General Counsel or Associate General Counsel to the Company, dated the Option Closing Date, relating to the Additional Shares to be purchased on such Options Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(e);

(e) an opinion and a negative assurance letter of Skadden, Arps, Slate, Meagher & Flom, LLP, counsel for the Underwriters, each dated the Option Closing Date, relating to the Additional Shares to be purchased on such Option Closing Date and otherwise to the same effect as the opinion required by Section 5(I)(f) hereof;

(f) a letter dated the Option Closing Date, in form and substance satisfactory to the Underwriters, from PricewaterhouseCoopers LLP, independent public accountants, substantially in the same form and substance as the letter furnished to the Underwriters pursuant to Section 5(I)(g) hereof; provided that the letter delivered on the Option Closing Date shall use a “cut-off date” not earlier than three business days prior to such Option Closing Date;

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(g) a letter dated the Option Closing Date, in form and substance satisfactory to the Underwriters, from Deloitte & Touche LLP, independent public accountants, substantially in the same form and substance as the letter furnished to the Underwriters pursuant to Section 5(I)(h) hereof; provided that the letter delivered on the Option Closing Date shall use a “cut-off date” not earlier than three business days prior to such Option Closing Date;

(h) such other documents as you may reasonably request with respect to the good standing of the Company, the due authorization and issuance of the Additional Shares to be sold on such Option Closing Date and other matters related to the issuance of such Additional Shares; and

(i) The representations and warranties of the Company contained herein shall be true and correct on and as of the Option Closing Date.

6. Covenants of the Company . The Company covenants with each Underwriter as follows:

(a) To furnish to you, without charge, a signed copy of the Registration Statement (including exhibits thereto and documents incorporated by reference therein) and to deliver to each of the Underwriters during the period mentioned in Section 6(e) or 6(f) below, as many copies of the Time of Sale Prospectus, the Prospectus, any documents incorporated by reference therein and any supplements and amendments thereto or to the Registration Statement as you may reasonably request. The Company will promptly advise the Underwriters of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any notice objecting to its use or the institution or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act or of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act.

(b) Prior to the completion of this offering, before amending or supplementing the Registration Statement, the Time of Sale Prospectus or the Prospectus, to furnish to you a copy of each such proposed amendment or supplement and not to file any such proposed amendment or supplement to which you reasonably object promptly after receipt thereof, provided that, if in the reasonable opinion of counsel for the Company, any such amendment or supplement shall be required by law or regulation to be used, that the Company shall be permitted to file such amendment or supplement after taking into account such comments as you may reasonably make on the content, form or other aspects of such amendment or supplement, and to file with the Commission within the applicable period specified in Rule 424(b) under the Securities Act any prospectus required to be filed pursuant to such Rule.

(c) To furnish to you a copy of each proposed free writing prospectus to be prepared by or on behalf of, used by, or referred to by the Company and not to use or refer to any proposed free writing prospectus to which you reasonably object, provided that, if in the reasonable opinion of counsel for the Company, any such amendment or supplement shall be required by law or regulation to be used, that the Company shall be permitted to file such amendment or supplement after taking into account such comments as you may reasonably make on the content, form or other aspects of such amendment or supplement.

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(d) Not to take any action that would result in an Underwriter being required to file with the Commission pursuant to Rule 433(d) under the Securities Act a free writing prospectus prepared by or on behalf of the Underwriter that the Underwriter otherwise would not have been required to file thereunder.

(e) If the Time of Sale Prospectus is being used to solicit offers to buy the Shares at a time when the Prospectus is not yet available to prospective purchasers and any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Time of Sale Prospectus in order to make the statements therein, in the light of the circumstances, not misleading, or if any event shall occur or condition exist as a result of which the Time of Sale Prospectus conflicts with the information contained in the Registration Statement then on file, or if, in the reasonable opinion of counsel for the Underwriters, it is necessary to amend or supplement the Time of Sale Prospectus to comply with applicable law, forthwith to prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to the dealers (whose names and addresses you will furnish to the Company) to which Shares may have been sold by you on behalf of the Underwriters, either amendments or supplements to the Time of Sale Prospectus so that the statements in the Time of Sale Prospectus as so amended or supplemented will not, in the light of the circumstances when the Time of Sale Prospectus is delivered to a prospective purchaser, be misleading or so that the Time of Sale Prospectus, as amended or supplemented, will no longer conflict with the Registration Statement, or so that the Time of Sale Prospectus, as amended or supplemented, will comply with applicable law.

(f) If, during such period after the first date of the public offering of the Shares as in the reasonable opinion of counsel for the Underwriters, the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is required by law to be delivered in connection with sales by an Underwriter or dealer, any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Prospectus in order to make the statements therein, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is delivered to a purchaser, not misleading, or if, in the reasonable opinion of counsel for the Underwriters, it is necessary to amend or supplement the Prospectus to comply with applicable law, forthwith to prepare, file with the Commission and furnish, at its own expense, to the Underwriters and to the dealers (whose names and addresses you will furnish to the Company) to which Shares may have been sold by you on behalf of the Underwriters and to any other dealers upon request, either amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Securities Act) is delivered to a purchaser, be misleading or so that the Prospectus, as amended or supplemented, will comply with applicable law.

(g) To endeavor to qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as you shall reasonably request; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction where it is not presently qualified or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

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(h) To apply the net proceeds from the sale of the Shares as described in each of the Time of Sale Prospectus and the Prospectus under the heading “Use of Proceeds.”

(i) To make generally available to the Company’s security holders and to you as soon as practicable an earnings statement covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the date of this Agreement which shall satisfy the provisions of Section 11(a) of the Securities Act and the rules and regulations of the Commission thereunder.

(j) If the third anniversary of the initial effective date of the Registration Statement occurs before all the Shares have been sold by the Underwriters, prior to the third anniversary to file a new shelf registration statement and to take any other action necessary to permit the public offering of the Shares to continue without interruption; references herein to the Registration Statement shall include the new registration statement declared effective by the Commission.

(k) If requested by the Representatives, to prepare a final term sheet relating to the offering of the Shares, containing only information that describes the final terms of the Shares or the offering in a form consented to by the Representatives, and to file such final term sheet within the period required by Rule 433(d)(5)(ii) under the Securities Act following the date the final terms have been established for the offering of the Shares.

(l) To not take, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of Shares.

(m) To use its commercially reasonable efforts to list the Shares and a number of Conversion Shares equal to the Maximum Number of Conversion Shares, subject to official notice of issuance, on the NYSE.

(n) To reserve and keep available at all times during the period from and including the Closing Date through and including August 1, 2020, free of preemptive or similar rights, a number of Conversion Shares equal to the Maximum Number of Conversion Shares less the aggregate number of Conversion Shares issued in connection with the conversion of Preferred Shares during such period.

(o) During the period from and including the date hereof through and including the earlier of (a) the purchase by the Underwriters of all of the Additional Shares and (b) the expiration of the Underwriters’ option to purchase Additional Shares, not to do or authorize or cause any act or thing that would result in an adjustment of the conversion rate of the Preferred Shares.

7. Expenses . Whether or not the transactions contemplated in this Agreement are consummated or this Agreement is terminated, the Company agrees to pay or cause to be paid all reasonable expenses incident to the performance of its obligations under this Agreement, including: (i) the fees, disbursements and expenses of the Company’s counsel and the Company’s accountants in connection with the registration and delivery of the Shares under the Securities Act and all other fees or expenses in connection with the preparation and filing of the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, the Prospectus, any free writing prospectus prepared by or on behalf of, used by, or referred to by the Company

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and amendments and supplements to any of the foregoing, including the filing fees payable to the Commission relating to the Shares (within the time required by Rule 456 (b)(1), if applicable), all printing costs associated therewith, and the mailing and delivering of copies thereof to the Underwriters and dealers, in the quantities hereinabove specified, (ii) all costs and expenses related to the transfer and delivery of the Shares to the Underwriters, including any transfer or other taxes payable thereon, (iii) the cost of printing or producing any Blue Sky or legal investment memorandum in connection with the offer and sale of the Shares under state securities laws and all expenses in connection with the qualification of the Shares for offer and sale under state securities laws as provided in Section 6(g) hereof, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection with such qualification and in connection with the Blue Sky or legal investment memorandum, (iv) all filing fees and the reasonable fees and disbursements of counsel to the Underwriters incurred in connection with the review and qualification of the offering of the Shares by the Financial Industry Regulatory Authority, (v) all fees and expenses in connection with the preparation and filing of the registration statement on Form 8-A relating to the Preferred Shares, if applicable, and all costs and expenses incident to listing the Shares and the Conversion Shares on the NYSE, (vi) the cost of, if any, printing certificates representing the Shares and the Conversion Shares, (vii) the costs and charges of any transfer agent, registrar or depositary, (viii) the costs and expenses of the Company relating to investor presentations on any “road show” undertaken in connection with the marketing of the offering of the Shares, including, without limitation, expenses associated with the preparation or dissemination of any electronic road show, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants engaged in connection with the road show presentations with the prior approval of the Company, travel and lodging expenses of the representatives and officers of the Company and any such consultants, and the cost of any aircraft chartered in connection with the road show, (ix) the document production charges and expenses associated with printing this Agreement, (x) all expenses in connection with any offer and sale of the Shares outside of the United States, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection with offers and sales outside of the United States and (xi) all other costs and expenses incident to the performance of the obligations of the Company hereunder for which provision is not otherwise made in this Section. It is understood, however, that except as provided in this Section, Section 9 entitled “Indemnity and Contribution,” and the last paragraph of Section 11 below, the Underwriters will pay all of their costs and expenses, including fees and disbursements of their counsel, stock transfer taxes payable on resale of any of the Shares by them and any advertising expenses connected with any offers they may make.

8. Covenants of the Underwriters . Each Underwriter severally covenants with the Company not to take any action that would result in the Company being required to file with the Commission under Rule 433(d) a free writing prospectus prepared by or on behalf of such Underwriter that otherwise would not be required to be filed by the Company thereunder, but for the action of the Underwriter.

9. Indemnity and Contribution. (a) The Company agrees to indemnify and hold harmless each Underwriter, each person, if any, who controls any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act and each affiliate of any Underwriter within the meaning of Rule 405 under the Securities Act from and against any and all losses, claims, damages and liabilities (including, without limitation, any

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legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus as defined in Rule 433(h) under the Securities Act, any Company information that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or the Prospectus or any amendment or supplement thereto, or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, except insofar as such losses, claims, damages or liabilities are caused by any such untrue statement or omission or alleged untrue statement or omission based upon information relating to any Underwriter furnished to the Company in writing by such Underwriter through you expressly for use therein, it being understood and agreed that the only such information furnished by the Underwriters consists of the information described in clause (b) below.

(b) Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, the directors of the Company, the officers of the Company who sign the Registration Statement and each person, if any, who controls the Company within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or any amendment thereto, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus as defined in Rule 433(h) under the Securities Act, any Company information that the Company has filed, or is required to file, pursuant to Rule 433(d) of the Securities Act, or the Prospectus (as amended or supplemented if the Company shall have furnished any amendments or supplements thereto), or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, but only with reference to information relating to such Underwriter furnished to the Company in writing by such Underwriter through you expressly for use in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus or the Prospectus or any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information in the seventh, ninth and tenth paragraphs of the Underwriting section in the preliminary prospectus and the Prospectus.

(c) In case any proceeding (including any governmental investigation) shall be instituted involving any person in respect of which indemnity may be sought pursuant to Section 9(a) or 9(b), such person (the “ indemnified party ”) shall promptly notify the person against whom such indemnity may be sought (the “ indemnifying party ”) in writing and the indemnifying party, upon request of the indemnified party, shall retain counsel reasonably satisfactory to the indemnified party to represent the indemnified party and any others the indemnifying party may designate in such proceeding and shall pay the fees and disbursements of such counsel related to such proceeding. In any such proceeding, any indemnified party shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless (i) the indemnifying party and the indemnified party shall have mutually agreed to the retention of such counsel or (ii) the named parties to any such proceeding (including any impleaded parties) include both the indemnifying party and the

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indemnified party and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is understood that the indemnifying party shall not, in respect of the legal expenses of any indemnified party in connection with any proceeding or related proceedings in the same jurisdiction, be liable for (i) the fees and expenses of more than one separate firm (in addition to one local counsel in each jurisdiction) for all Underwriters and all persons, if any, who control any Underwriter within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act or who are affiliates of any Underwriter within the meaning of Rule 405 under the Securities Act and (ii) the fees and expenses of more than one separate firm (in addition to one local counsel in each jurisdiction) for the Company, its directors, its officers who sign the Registration Statement and each person, if any, who controls the Company within the meaning of either such Section, and that all such fees and expenses shall be reimbursed as they are incurred. In the case of any such separate firm for the Underwriters and such control persons and affiliates of any Underwriters, such firm shall be designated in writing by the Representatives. In the case of any such separate firm for the Company, and such directors, officers and control persons of the Company, such firm shall be designated in writing by the Company. The indemnifying party shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party from and against any loss or liability by reason of such settlement or judgment. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened proceeding in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party, unless (i) such settlement includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such proceeding and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party.

(d) To the extent the indemnification provided for in Section 9(a) or 9(b) is unavailable to an indemnified party or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each indemnifying party under such paragraph, in lieu of indemnifying such indemnified party thereunder, shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other hand from the offering of the Shares or (ii) if the allocation provided by clause 9(d)(i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause 9(d)(i) above but also the relative fault of the Company on the one hand and of the Underwriters on the other hand in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other hand in connection with the offering of the Shares shall be deemed to be in the same respective proportions as the net proceeds from the offering of the Shares (before deducting expenses) received by the Company and the total underwriting discounts and commissions received by the Underwriters bear to the aggregate price at which the Shares are offered to the public, as set forth in the Prospectus. The relative fault of the Company on the one hand and the Underwriters on the other hand shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to

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information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Underwriters’ respective obligations to contribute pursuant to this Section 9 are several in proportion to the respective number of Shares they have purchased hereunder, and not joint.

(e) The Company and the Underwriters agree that it would not be just or equitable if contribution pursuant to this Section 9 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in Section 9(d). The amount paid or payable by an indemnified party as a result of the losses, claims, damages and liabilities referred to in Section 9(d) shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 9, no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Shares underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The remedies provided for in this Section 9 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any indemnified party at law or in equity.

(f) The indemnity and contribution provisions contained in this Section 9 and the representations, warranties and other statements of the Company contained in this Agreement shall remain operative and in full force and effect regardless of (i) any termination of this Agreement, (ii) any investigation made by or on behalf of any Underwriter, any person controlling any Underwriter or any affiliate of any Underwriter or by or on behalf of the Company, its officers or directors or any person controlling the Company and (iii) acceptance of and payment for any of the Shares.

10. Termination . The Underwriters may terminate this Agreement by notice given by you to the Company, if after the execution and delivery of this Agreement and prior to the Closing Date (i) trading generally shall have been suspended or materially limited on, or by, as the case may be, any of the NYSE or the NASDAQ Global Market, (ii) trading of any securities of the Company shall have been suspended on any exchange or in any over-the-counter market, (iii) a material disruption in securities settlement, payment or clearance services in the United States shall have occurred, (iv) any moratorium on commercial banking activities shall have been declared by Federal or New York State authorities or (v) there shall have occurred any outbreak or escalation of hostilities, or any change in financial markets or any calamity or crisis that, in your judgment, is material and adverse and which, singly or together with any other event specified in this clause (v), makes it, in your judgment, impracticable or inadvisable to proceed with the offer, sale or delivery of the Shares on the terms and in the manner contemplated in the Time of Sale Prospectus or the Prospectus.

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11. Effectiveness; Defaulting Underwriters . This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

If, on the Closing Date or an Option Closing Date, as the case may be, any one or more of the Underwriters shall fail or refuse to purchase Shares that it has or they have agreed to purchase hereunder on such date, and the aggregate number of Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase is not more than one-tenth of the aggregate number of the Shares to be purchased on such date, the other Underwriters shall be obligated severally in the proportions that the number of Firm Shares set forth opposite their respective names in Schedule I bears to the aggregate number of Firm Shares set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as you may specify, to purchase the Shares which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date; provided that in no event shall the number of Shares that any Underwriter has agreed to purchase pursuant to this Agreement be increased pursuant to this Section 11 by an amount in excess of one-ninth of such number of Shares without the written consent of such Underwriter. If, on the Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Firm Shares which it or they have agreed to purchase hereunder on such date and the aggregate number of Firm Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Firm Shares to be purchased on such date, and arrangements satisfactory to you and the Company for the purchase of such Firm Shares are not made within 36 hours after such default, this Agreement shall terminate without liability on the part of any non-defaulting Underwriter or the Company. In any such case either you or the Company shall have the right to postpone the Closing Date, but in no event for longer than seven days, in order that the required changes, if any, in the Registration Statement, in the Time of Sale Prospectus, in the Prospectus or in any other documents or arrangements may be effected. If, on an Option Closing Date, any Underwriter or Underwriters shall fail or refuse to purchase Additional Shares and the aggregate number of Additional Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Additional Shares to be purchased on such Option Closing Date, the non-defaulting Underwriters shall have the option to (i) terminate their obligation hereunder to purchase the Additional Shares to be sold on such Option Closing Date or (ii) purchase not less than the number of Additional Shares that such non-defaulting Underwriters would have been obligated to purchase in the absence of such default. Any action taken under this paragraph shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement.

If this Agreement shall be terminated by the Underwriters, or any of them, because of any failure or refusal on the part of the Company to comply with the terms or to fulfill any of the conditions of this Agreement, or if for any reason the Company shall be unable to perform its obligations under this Agreement, the Company will reimburse the Underwriters or such Underwriters as have so terminated this Agreement with respect to themselves, severally, for all out-of-pocket expenses (including the fees and disbursements of their counsel) reasonably incurred by such Underwriters in connection with this Agreement or the offering contemplated hereunder.

12. Entire Agreement . (a) This Agreement, together with any contemporaneous written agreements and any prior written agreements (to the extent not superseded by this Agreement) that relate to the offering of the Shares, represents the entire agreement between the Company and the Underwriters with respect to the preparation of any preliminary prospectus, the Time of Sale Prospectus, the Prospectus, the conduct of the offering, and the purchase and sale of the Shares.

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(b) The Company acknowledges that in connection with the offering of the Shares: (i) the Underwriters have acted at arm’s length, are not agents of, and owe no fiduciary duties to, the Company or any other person, (ii) the Underwriters owe the Company only those duties and obligations set forth in this Agreement and prior written agreements (to the extent not superseded by this Agreement), if any, and (iii) the Underwriters may have interests that differ from those of the Company. The Company waives to the full extent permitted by applicable law any claims it may have against the Underwriters arising from an alleged breach of fiduciary duty in connection with the offering of the Shares.

13. Counterparts . This Agreement may be signed in two or more counterparts, each of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument.

14. Applicable Law . This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the internal laws of the State of New York.

15. Headings . The headings of the sections of this Agreement have been inserted for convenience of reference only and shall not be deemed a part of this Agreement.

16. Compliance with USA Patriot Act . In accordance with the requirements of the USA PATRIOT Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), each of the Underwriters is required to obtain, verify and record information that identifies its clients, including the Company, which information may include the name and address of its clients, as well as other information that will allow each of the Underwriters to properly identify its clients.

17. Notices . All communications hereunder shall be in writing and effective only upon receipt and if to the Underwriters shall be delivered, mailed or sent to you at the address set forth in Schedule II hereto; and if to the Company shall be delivered, mailed or sent to the address set forth in Schedule II hereto.

[signature pages follow]

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[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]

[Signature page to Crown Castle International Corp. Underwriting Agreement]