The French Law Firm dedicated to Patent Litigation
Why patent litigation calls for a dedicated firm
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Patent disputes are concentrated before a small number of courts: the Paris Judicial Court, which has exclusive jurisdiction in France, the Unified Patent Court since June 2023, and the European Patent Office for opposition. The same family of titles can be attacked before all three, on timetables that do not coincide.
The actions themselves are few and sharply defined: infringement, revocation, provisional measures, saisie-contrefaçon, entitlement claims, employee inventions, and disputes over licences and FRAND undertakings on standard essential patents. Each has its own conditions of admissibility, its own deadlines and its own economy of proof.
The firm works on patent litigation and on the questions that attach directly to it: evidence, trade secrets, employee inventions, licences and FRAND undertakings.
Nous plead in claim and in defence, before the French courts and before the Unified Patent Court, and we coordinate parallel proceedings run abroad.
A Paris boutique serving technology companies
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The firm serves leading companies whose legal needs have a strong scientific and technological component.
Dhenne Avocats is thus characterized by its focus on patent litigation, high value-added services at a fair price, responsiveness, and willingness to move forward together with its clients.
Our attorneys, who have recognized expertise, represent our clients before the French, European, and arbitration courts. They act in various technical sectors (e.g., mechanical, electronic, chemical), mainly in complex high value-added litigation (i.e., IT and life sciences).
How we work
Reading the patent, choosing the forum
Before acting or responding, three questions decide what follows: does the patent withstand the closest prior art , can infringement be shown claim by claim, and before which court should the case be brought.
The choice of forum is largely irreversible. The Paris Judicial Court, the Unified Patent Court and opposition before the European Patent Office do not offer the same timelines, the same territorial reach or the same exposure to the risk of revocation. We document this trade-off before filing suit, and we revisit it when the opponent opens a second front.
Litigation, urgency and evidence
A writ of summons received, a saisie-contrefaçon carried out at your premises, a product launch blocked by a competitor’s patent : the first decisions are taken within days and shape everything that follows. We conduct proceedings before the Paris Judicial Court and before the Unified Patent Court, and coordinate the fronts opened abroad.
What we actually run:
Gathering evidence
of infringement with
a seizure of counterfeit goods
Introducing an invalidation action of a third party's patent before a court Defend you against a patent infringement
Defend you against a patent infringement
Defend you against an infringement of your trade secrets, particularly in the event of a seizure of counterfeit goods
Help you fight against unfair competition, particularly in the event of parasitism
Patent licences and contracts
A patent agreement is drafted with the dispute it will have to avoid, or win, in mind. We negotiate and draft the agreements that transfer, share or exploit patents and know-how :
Partnership agreement including aspects of intellectual property.
A patent dispute under way or imminent?
We act for claimants and defendants alike, before the Paris Judicial Court and before the Unified Patent Court. A first discussion will tell you whether the matter falls within our practice and on what timetable it should be brought.
Frequently asked questions about our firm
Dhenne Avocats is a Paris firm founded in 2018 by Matthieu Dhenne, devoted entirely to patent litigation.
Matthieu Dhenne has been a member of the Paris Bar since 2014. He is ranked by Legal 500 (Tier 1, patent litigation) and by Leaders League (Highly regarded in “Patents: litigation” and in “Patents: pharma, biotech and life sciences litigation”).
He teaches on the Master 2 in Industrial Property at Université Panthéon-Assas, serves as French correspondent for the Kluwer Patent Blog and publishes regularly on patent law, in particular on the patentability of computer-implemented inventions. The firm is consulted by the French authorities on patent law reform projects.
Yes. We work in French and in English, either as lead counsel or as French correspondent to a foreign law firm or patent attorney.
A patent dispute is rarely confined to one country. We handle the French and UPC parts of a pan-European dispute, in coordination with counsel running parallel proceedings in Germany, the Netherlands or the United Kingdom, and with those conducting opposition proceedings before the European Patent Office.
The saisie-contrefaçon is the evidence-gathering measure foreign counsel most often come to France for. We prepare it, we carry it out and we defend it at the référé-rétractation stage.
We act in disputes with a strong technical component, in the sectors where value is defended through patents.
Our cases involve telecommunications and standard essential patents, software and computer-implemented inventions, pharmaceuticals, biotechnology and medical devices, chemistry, electronics and mechanical engineering.
We also handle licence agreements, employee inventions and trade secrets, which almost always precede or follow the litigation.
Recommendations
They recommend us
Clients and peers from around the world on their work with the firm.
« Matthieu is one of the most brilliant patent litigators I met in Europe. Very deep legal and technical understanding with a strong client-focused approach. Matthieu is creative by essence, and able to design successful legal strategies. »
« Matthieu is an accomplished and astute French patent litigator and counselor, with deep and growing experience across French courts and the new Unified Patent Court. His expertise on patent litigation is strongly recommendable. »
« I would highly recommend Matthieu and his excellent team for inventor remuneration issues. He has handled a quite delicate inventor claim with well-founded knowledge, excellent writing skills and great sense for underlying strategy. »
« Matthieu, a competent professional with the desire to always get involved and the aim of bringing home the result. A truly deep knowledge of IP law. »
Awards & rankings
Dhenne Avocats and its founder, Matthieu Dhenne, are consistently listed in the leading directories.