Enforcing your patent


Patent litigation


What should you do if you receive a letter of formal notice or a letter complaining about your use of a third party’s patent?


It is best to be careful in your response. First it is not advisable to respond yourself. Indeed, the communications between your company and the third party may be used in court if the dispute subsequently becomes contentious.

At this stage, you should seek assistance of our team of intellectual property attorneys, who will be able to analyze whether or not the claim is well-founded, the validity of the patent in dispute and your means of action.


What’s more, communications between IP attorneys and/or law firms are confidential, which makes it possible to discuss a coexistence or an out-of-court settlement without the risk of written documents being made public in a court of law.

Consulting a law firm specializing in intellectual property can also give you a clearer idea of what you are accused of, whether or not you are really at fault, whether or not your opponent’s claim is well-founded, and what you can do about it. In many cases, there are legal means of responding to what is being asked.

On the other hand, if common ground is found with the third party, each party will have obligations to fulfill to ensure that the situation is, and remains, peaceful. It may be useful to formalize these mutual commitments so that each party is bound. Here again, the assistance of an IP law professional is essential to prevent any pitfalls.

Alongside these steps, it’s also important to be prepared for the possible consequences of these claims, such as a writ of summons or seizure for counterfeiting. For the latter, please consult our dedicated page.

Our teams are at your disposal to give you an initial opinion by e-mail or telephone and to consider together the best way to support you, in line with your strategic objectives.

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Intellectual property experts close to you and your needs

Since 1866, Brandon IP, formerly known as Blétry Frères, has been helping its customers to protect and defend their intellectual property rights. We are one of the oldest industrial property firms in France. We support companies of all sizes and individuals in protecting their inventions in a fully customized way, tailored to their needs. As proof of our expertise, Brandon IP is ranked among the top French IP firms by Leaders League (Décideurs Magazine).

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Our patent team is made up of patent attorneys and expert patent engineers in various technical fields and legal assistants. The attorneys are in charge of advising, prior art searches, freedom to operate, drafting patent applications, etc.

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To learn more about our services, please do not hesitate to contact us.


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