UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

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SCHEDULE 14A

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InterDigital Communications Corporation

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InterDigital Communications Corporation

781 Third Avenue

King of Prussia, PA 19406

Supplement to Proxy Statement

May 4, 2005

Dear Shareholders:

Yesterday, InterDigital Communications Corporation announced a change in leadership that we believe will enable the Company to move confidently into the future and build on its recent successes. Mr. William J. Merritt, who has led the Company’s patents and licensing group since 2001, has been appointed InterDigital’s President and Chief Executive Officer, effective immediately. Additionally, Mr. Merritt has been appointed to InterDigital’s Board of Directors, to serve for a term expiring at the 2006 Annual Meeting of Shareholders. Mr. Merritt, a member of InterDigital’s executive team, succeeds Howard E. Goldberg.

Most recently, Mr. Merritt has served as President of InterDigital Technology Corporation and General Patent Counsel. Mr. Merritt is a seasoned executive who brings a wealth of industry and business experience as well as an intimate knowledge of the InterDigital organization and our business model to his new role. Mr. Merritt has demonstrated great creativity and business savvy in advancing InterDigital’s licensing program and technology solutions. I am extremely confident in Mr. Merritt’s ability to continue to build value for our shareholders. We look forward to a smooth transition.

Sincerely,

Harry G. Campagna

Harry G. Campagna

Chairman of the Board