Claims

Patent claims are the part of the application that defines the subject matter for which protection is sought. They delimit the proprietor’s monopoly. Under Article L. 613-2 of the French Intellectual Property Code and Article 69 of the European Patent Convention, the extent of the protection conferred by a patent is determined by the claims, the description and drawings being used to interpret them. All validity and infringement litigation revolves around the claims.

Types of patent claims

First, product claims, which cover an object, a substance or a composition. Next, process claims, which cover a sequence of steps and whose protection extends to the product directly obtained. Then use or application claims, frequent in pharmaceuticals for a new therapeutic indication. Finally, a distinction is drawn between independent claims, which define the invention by its essential features, and dependent claims, which add particular features and provide fallback positions in the event of partial revocation.

Requirements applicable to claims

Claims must be clear, concise and supported by the description. Lack of clarity is examined during prosecution but is not, as such, a standalone ground for revocation of a granted patent. By contrast, a claim whose subject matter extends beyond the application as filed, or which is insufficiently disclosed, is liable to revocation. The drafting rules are set out on the website of the European Patent Office and on Légifrance.

Claim interpretation in litigation

The court interprets the claims by striking a balance between fair protection for the proprietor and legal certainty for third parties, taking account of equivalents in accordance with the Protocol on the Interpretation of Article 69. Infringement by equivalence may cover variants satisfying the applicable legal test. Performing the same function alone is not a universal test. The Unified Patent Court has made clear that it interprets the claims in the same way when assessing validity and infringement. In practice, a request for limitation allows the patent claims to be redefined in the face of prior art. The firm analyses and argues these questions before the Paris judicial court and the UPC, as presented on the page patent litigation.

Key takeaways

Everything turns on the claim: it fixes the extent of the monopoly, serves as the yardstick for infringement and as the object of the validity review. Broad drafting exposes the patent to revocation. Narrow drafting lets workarounds through. In litigation, the reading adopted is that of the person skilled in the art at the relevant date, the description and drawings serving to interpret the claims, not to extend them.