Picture of Willem Hoorneman

Willem Hoorneman

Managing Partner

Atrium - Parnassusweg 737
1077 DG Amsterdam
PO Box 94700
1090 GS Amsterdam
Languages English, Dutch

Willem Hoorneman has been managing partner of CMS in the Netherlands since 2016. He is a member of the IPC/TMC Practice Group, especially within Life Sciences. With energy and commitment Willem heads the Life Sciences Group in the Netherlands which stands for new growth.

With more than 30 years of experience in intellectual property (IP) and author of the patent chapters in the leading handbook on software protection in the Netherlands, Willem is considered a pre-eminent IP lawyer, and one of the very best in the field of patent law. In addition, for years he was editor-in-chief of the BMM Bulletin, a leading magazine on trademark and design law in the Benelux. Willem is internationally recognized for his expertise.

Willem has earned an excellent reputation as a litigator for various IP matters. He is also a panelist of the World Intellectual Property Organization (WIPO) for domain name alternative dispute resolution.

Follow Willem on Twitter and keep up to date on the latest news concerning Life Sciences: @wajh0107.

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Willem Hoorneman is a key client contact for this practice.

Chambers Europe, 2018

Willem Hoorneman offers strong experience in patent law as well as handling many other general intellectual property issues.

Chambers Global, 2017

Willem Hoorneman is recommended.

The Legal 500, 2017

His recent work spans many areas in IP law, including handling trade mark cases on behalf of international companies, design right infringements and patent litigation.

Chambers Europe, 2017


  • Dutch Law, University of Amsterdam

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  • Head of CMS Life Sciences Sector Group

  • Managing Partner

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