Exhibit 16.1
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PricewaterhouseCoopers LLP | |
750 B Street, Suite 2900 | |
San Diego CA 92101-8122 | |
Telephone (619) 744 8000 | |
Facsimile (619) 744 8400 |
June 13, 2007
Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549
Commissioners:
We have read the statements made by Acacia Research Corporation (copy attached), which we understand will be filed with the Securities and Exchange Commission, pursuant to Item 4.01 of Form 8-K, as part of the Form 8-K of Acacia Research Corporation dated June 11, 2007. We agree with the statements concerning our Firm in such Form 8-K.
Very truly yours,
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PricewaterhouseCoopers LLP