Could Description Amendments Made During Prosecution At The European Patent Office Affect U.S. Litigation?

• Published date: 08 December 2021
• Subject Matter: Intellectual Property, Patent
• Law Firm: Finnegan, Henderson, Farabow, Garrett & Dunner, LLP
• Author: Ms Maeve O'Flynn and William C. Neer

Earlier this year, the European Patent Office (EPO) updated some of its Guidelines for Examination in a way that potentially could affect U.S. patent litigation. These Guidelines instruct European patent examiners (and the public) on how the patent prosecution process works'much like the United States Patent and Trademark Office's (USPTO's) Manual of Patent Examining Procedure. For example, the Guidelines detail what form a patent application must be in, what happens during a prior art search, and perhaps most importantly, what should be included in an application. Guideline F-IV 4.3 particularly focuses on the form, contents, and clarity of the claims.

A Stricter Approach

Article 84 of the EPC provides that the "claims shall define the matter for which protection is sought. They shall be clear and concise and be supported by the description." Guideline F-IV 4.3 interprets this Article to include a prohibition against any inconsistencies between the claims and the description that "may throw doubt on the extent of protection and therefore render the claim unclear or unsupported."

Previously, Guideline F-IV 4.3 provided that if there were inconsistencies between the description (or specification in the United States) and the claims, then the description needed to be amended to clarify which portions of the description fell outside the scope of the claims. Such amendments would usually include identifying embodiments/inventions not falling within the scope of the claims. It was typically possible to avoid deleting subject matter.

The amended Guideline appears to require a stricter approach, stating that all inconsistent and unsupportive material must be deleted from the description entirely. It provides:

Where parts of the description give the reader the impression that they disclose ways to carry out the invention but are not or, due to amendments to the claims, are no longer encompassed by the wording of the claims, these parts often throw doubt on the scope of protection and therefore render the claims unclear . . . . Embodiments in the description which are no longer covered by the independent claims must be deleted . . . unless these embodiments can reasonably by considered to be useful for highlighting specific aspects of the amended claims.

The effect of this amendment on European prosecution is still unclear. But it already seems that examiners are more likely to require the deletion of subject matter unless a good argument can be made that it is...