Could Description Amendments Made During Prosecution at the European Patent Office Affect U.S. Litigation?

“In light of the amended European Patent Office Guidelines, applicants should take extra care when responding to objections of inconsistency between the description and claims.” 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 helpful in the interpretation of the allowable claims.

For those inventors or companies that have, or aspire to have, an international presence, it is important to consider patent portfolios as a whole rather than focusing on each patent application individually.

When a patent owner sues someone for patent infringement in the United States, she must prove that the alleged infringing product contains or performs every limitation found in the asserted claims. At times, this requires that a court construe claim terms to determine their meanings. Prosecution history estoppel can prevent a patent owner from claiming inventions that do not fall within the scope of the claims or that were explicitly forfeited during prosecution. This doctrine is not necessarily limited to only statements made during U.S. prosecution.

The Federal Circuit has held that “representations to foreign patent offices should be considered . . . when [they] comprise relevant evidence.” Caterpillar Tractor Co. v. Berco, S.p.A., 714 F.2d 1110, 1116 (Fed. Cir. 1983). Although the Court is cautious to do so, it still may consider statements made to other patent offices when 1). the statement was made in an official proceeding where the patentee had every incentive to exercise care in characterizing the scope of its invention; 2). the foreign patent is related to and/or shares an identical claim with the asserted U.S. patent; and 3). the statement was a blatant admission, “consistent with the claims and the invention described in the specification,” or not related to a unique aspect of foreign patent law. See Apple Inc. v. Motorola, Inc., 757 F.3d 1286, 1312–13 (Fed. Cir. 2014).

What Will U.S. Courts Do?

This begs the question: could description amendments made under Guideline F-IV 4.3 affect U.S. litigation? U.S. courts have yet to grapple with this specific question.

Assume that an applicant submitted identical descriptions and claims to the USPTO and the EPO. But during prosecution, the EPO required the applicant to delete material in the description to ensure consistency between the claims and the description. Both applications then issued with identical claims. Parts one and two of this inquiry are easily met. A court’s hardest task is to determine whether the statement was a blatant admission, “consistent with the claims and the invention described in the specification,” or not related to a unique aspect of foreign patent law.

In this hypothetical, a court could find that description amendments are blatant admissions. See Gillette Co. v. Energizer Holdings, Inc., 405 F.3d 1367, 1374 (Fed. Cir. 2005) (holding that patentee’s statements to the EPO regarding claim scope could be used in claim construction because they were blatant admissions). Because description amendments delete embodiments that are outside the scope of the claims, a court could interpret them to be blatant admissions of claim scope of identical claims. Courts could similarly apply this same logic to find that description amendments are made to be consistent with the claims and invention, and thus, they are relevant to understanding the scope of the claims in the U.S. patent.

Whether description amendments are “unique to foreign patent law” may be a closer call. It is rare for the specification to be amended during U.S. prosecution. In fact, U.S. examiners do not have the authority to require an applicant to delete material in the specification that is not covered in the claims. Thus, a court could conclude that the EPO’s description amendment requirements are so different from U.S. patent law, that an applicant’s response to such a requirement should not impact the scope of the U.S. patent. Claims, however, define the “metes and bounds” of the invention. They are not unique to foreign patent law. Therefore, a court may find that the deletion is not “a statement related to unique aspects of foreign patent law” because it was a statement about claim scope.

Take Care

In light of the amended EPO Guidelines, applicants should take extra care when responding to objections of inconsistency between the description and claims. This lesson, however, is not limited to the EPO. Patent owners or applicants should always carefully consider how they draft patents and respond to rejections no matter where they are seeking protection because their statements may be used against them in other jurisdictions.

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Join the Discussion

2 comments so far.

  • [Avatar for Particularly Pointing Out]
    Particularly Pointing Out
    December 5, 2021 03:21 pm

    A client recently escaped the ‘inescapable trap’.

    If what happens at the EPO counts for inequitable conduct in the USA, why shouldn’t what happens at the EPO impact litigation in the USA?

  • [Avatar for MaxDrei]
    November 30, 2021 04:36 pm

    Well, thanks for this. I have to say though that the EPO has always insisted upon strict conformity between what the claims define as the invention and what the specification describes as the invention, so any narrowing amendment during prosecution at the EPO has always made US attrneys nervous. I’m intrigued by the thought that, for a US court, expunging all trace of an illustrated embodiment IS an admission whereas retaining that drawing figure together with text in the specification stating that it is NOT an embodiment of the claimed invention is NOT any such admission. Frankly, I should have thought the safer course to be to clean out the embodiments outside the literal wording of the claim and leave no trace of them in the as issued US patent.

    In other words, is not an explicit admission made in the specification of the patent more dangerous than a letter to the EPO Examiner which maintains that it is the quest for more clarity which explains the excision of one or other drawing figure and passage of the escription.

    Be that as it may though, I welcome postings on life at the EPO. The reason why the EPO gets so excited about conformity is that once the application goes to issue, indefiniteness (want of clarity) is not a ground of invalidity. Accordingly, the EPO places great weight on allowing through to grant only those cases that make it unambiguously clear what the protected subject matter is, and what it is not.