William J. Thomashower

Counsel at
Pryor Cashman

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William Thomashower is a member of Pryor Cashman’s Intellectual Property Group. With more than 40 years of experience litigating complex IP cases, he represents clients in state and federal courts, before arbitration panels and in matters before the U.S. Patent and Trademark Office.

Bill counsels global brands, consumer goods companies, luxury goods manufacturers, digital media companies, web-based businesses, entertainment and publishing companies and B2B industrial entities on all aspects of trademark law, including selection, prosecution, policing and litigation. He has extensive experiencing handling cases involving dilution, cybersquatting, trade dress and false advertising claims.

Bill also advises on a wide range of copyright issues, including registration, licensing and infringement, as well as patent validity and infringement matters.

Additionally, he counsels clients on defamation and constitutional issues, antitrust claims and the regulations governing physicians and healthcare providers.

His recent experience includes:

  • Obtaining summary judgment of non-infringement of a design patent for packaging after completing all discovery and expert reports for trial;
  • Successfully defending, through appeal, a national internet retailer against a brand owner’s trademark and copyright infringement claims;
  • Successfully defending a Fortune 500 electronic banking company in numerous patent infringement litigations brought by patent assertion entities;
  • Obtaining a jury verdict of non-infringement for a client using a trademark to describe genuine merchandise in a case involving disputed ownership with former partners;
  • Successfully halting the attempted misappropriation of a famous New York nightclub’s name through an emergency motion for preliminary injunction.

Industry Recognition

Bill is a frequent lecturer and writer on issues involving intellectual property, licensing and legal ethics, among other subjects. He serves on the New York Intellectual Property Law Association’s (“NYIPLA”) Trademark and Programs Committees.

Practice Areas

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