Auxiliary requests

Auxiliary requests are the amended sets of claims that a patent applicant or proprietor submits in the alternative, in case its main request is not allowed. They are submitted in a hierarchical order and examined in turn, the office or court ruling on the first allowable request. They lie at the heart of patent defence in opposition proceedings before the European Patent Office (EPO), on appeal and before the Unified Patent Court (UPC).

Practice before the EPO

Before the Examining Division as before the Opposition Division, each auxiliary request must meet the requirements of the European Patent Convention (EPC), and in particular must not extend the subject matter beyond the content of the application as filed or, after grant, extend the protection conferred. The Division examines the requests in the order set by the party and maintains the patent in the amended form corresponding to the first request that complies with the Convention. Before the Boards of Appeal, the Rules of Procedure applicable since 2020 have tightened the restrictions on the late filing of new requests, which must in principle be included in the statement of grounds of appeal or the reply to it.

Practice before the UPC and the French courts

Before the Unified Patent Court, a proprietor facing an invalidity action or a counterclaim for invalidity may file an application to amend the patent, accompanied by auxiliary requests. The Court requires that their number remain reasonable in the circumstances of the case and that each one be justified. Before the French courts, the proprietor may limit its patent during the proceedings by amending its claims, the patent as limited then becoming the subject of the invalidity action.

Strategic issues

Building auxiliary requests requires anticipating the opponent’s objections and ranking the fallback positions from the broadest to the narrowest, while maintaining consistency with the alleged infringement. A request that is too broad exposes the patent, while one that is too narrow may no longer cover the allegedly infringing product. The proprietor must also bear in mind that a fallback position accepted before one office or court may be held against it in parallel proceedings concerning the same patent.

Key points

Auxiliary requests are the proprietor’s main resource for saving its patent against a validity attack. Their effectiveness depends on early preparation, since offices and courts increasingly penalise requests that are late or too numerous. They should be built as soon as the opposition or counterclaim is received, checking for each one its basis in the application as filed and its scope in relation to the alleged infringement.

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This glossary entry is general in scope and does not constitute legal advice.

Dhenne Avocats litigates patent disputes before the Paris Judicial Court, the Paris Court of Appeal and the Unified Patent Court. Where the question arises in a real case, the useful moment is almost always before proceedings are issued.

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