Delaware                                   95-4405754
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(State of Incorporation or Organization)    (I.R.S. Employer Identification no.)

500 Newport Center Drive, Newport Beach, CA                 92660
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  (Address of Principal Executive Offices)                (Zip Code)

Securities to be registered pursuant to Section 12(b) of the Act:

Title of Each Class                               Name of Each Exchange on Which
to be so Registered                               Each Class is to be Registered
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      None                                                    N/A

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c), please check the following box. [ ]

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d), please check the following box. |X|

Securities Act registration statement file number to which this form relates: 333-87654

Securities to be registered pursuant to Section 12(g) of the Act:

INFORMATION REQUIRED IN
REGISTRATION STATEMENT

ITEM 1. DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED

Descriptions of the Acacia Research - CombiMatrix Common Stock and the Acacia Research - Acacia Technologies Common Stock are contained in the Registrant's Registration Statement on Form S-4 (File No. 333-87654) (the "Form S-4 Registration Statement") and are incorporated herein by reference, including without limitation the section entitled "Description of AR-CombiMatrix Stock and AR-Acacia Technologies Stock" at page 78 of the Form S-4 Registration Statement.

ITEM 2. EXHIBITS

The following exhibits are filed as a part of this registration statement:

1. Restated Certificate of Incorporation of the Registrant (incorporated by reference from Exhibit 3.2 to the Form S-4 Registration Statement);

2. Amended and Restated Bylaws of the Registrant (incorporated by reference from the Registrant's Quarterly Report on Form 10-Q filed on August 10, 2001);

3. Common Stock Policies of the Registrant (incorporated by reference from Annex C to the Proxy Statement and Prospectus which forms a part of the Form S-4 Registration Statement).

SIGNATURES

Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the Registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereto duly authorized.

Dated:  December 19, 2002            By:  /s/ Paul R. Ryan
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                                     Name: Paul R. Ryan
                                     Title: Chairman and Chief Executive Officer