• +33 1 53 10 91 95
  • lawoffices@kopacz-paris.fr
  • fr
  • en

The firm

Cabinet Kopacz

A Boutique firm dedicated to Intellectual Property

Founded in 1980 by William James Kopacz, the firm handles all intellectual property and associated matters, from obtaining and maintaining rights to their defense before French and European jurisdictions.

Our practice has led us to develop a particular expertise in the protection and defense of famous brands, particularly in the field of new technology.

The firm is also known for finding pre-litigation solutions to complex conflicts and negotiating agreements.

A firm with recognized litigation expertise

Over the last 20 years we have handled more than 4000 cases, including more than 300 cases before the French and European courts.

The firm has a success rate of more than 80% for cases that actually went to judgment in the French and European courts.


A bilingual and responsive team

Our team is made up of bilingual attorneys (French/English), most of them trained in both the French and the Common Law traditions.

This feature facilitates communication with foreign clients and correspondents and allows us to shed light on the specificities of French and European Union law. It also allows us to intervene in all proceedings before the European Union jurisdictions.

The personal attention which we accord to clients, coupled with concrete results in the courtroom, have led some of the most prestigious companies and law firms in the world to entrust us with their intellectual Property representation in France and at the European Union Intellectual Property Office.

What our clients say about us

William James Kopacz is “efficient, responsive, proactive and wins many, many cases”

He is very bottom-line oriented and provides solid, business-focused legal advice. I trust his guidance implicitly and have been working with him and his team for 25 years.

World Trademark Review - the World's Leading Trademark Professionals 2022

The “youthful, energetic and driven” trademark practice at this boutique “impresses with its success rate in contentious matters”. Internationally admired as “great to work with”, the firm is “quick, precise and very good at proving the repute of a famous mark and enforcing it against dilution”.
Eponymous partner William James Kopacz has reaped renown for his defence of marks owned by US high-technology companies, among other matters.

World Trademark Review – The World’s Leading Trademark Professionals 2012