Patent joint defence agreements: Hidden pitfalls


Paul J. Sutton

It is not unusual for several companies within an industry to be named as co-defendants within a patent infringement lawsuit.

In such cases the complaint will include allegations of infringement of the same patent or patents. This will be so even though the products or services marketed by the defendants may differ from one another. In the case of accused infringing products, for example, the designs of the defendants can vary in any number of respects, even if their intended purposes are identical or similar.

The natural impulse of defendants’ managements facing a common enemy is to want to share information, resources, and strategies. If non-lawyers in one co-defendant reach out to individuals in other co-defendants, despite good intentions, their communications will in most cases not be privileged and will open these individuals up to examinations under oath in oral depositions, for example. The wiser approach will be for management to confer with their counsel, and thereafter permit communications between the companies to take place on the part of attorneys.

One defendant’s preferred Markman interpretation of a patent may be poison to another defendant’s position.

patent, co-defendants, infringement