When is it necessary to amend the description of a patent post-grant (T2391/18)

The decision of the EPO Board of Appeal in T 2391/18 considered whether non-conformity of the description with the claims can, by itself, invalidate a granted patent. The Board of Appeal concluded that a discrepancy between the claims and the description is a clarity issue, and therefore not a ground for Opposition by itself. 

Description amendments: What is all the fuss about?

A peculiarity of EPO patent practice is the requirement for applicants to amend the description in line with the amended claims. In the past, the Examining Division permitted applicants to take a light-touch with regards these amendments. However, for reasons known only to itself, the EPO introduced new Guidelines in 2021 that dramatically increased the amount of description amendments required (F-IV, 4.3). Making these substantial amendments can be costly and time consuming for applicants and may also affect interpretation of the claims by national courts. 

Amending the description

There is currently disagreement among the Boards of Appeal on whether the requirement for applicants to amend the description in line with the claims has legal basis. A number of Boards of Appeal have proposed Article 84 EPC and/or Article 69 EPC as legal basis for the description amendment requirement. Article 84 EPC states that "the claims shall define the matter for which protection is sought and that they shall be clear and concise and be supported by the description". Article 69 EPC states that "the extent of the protection conferred by a European patent or a European patent application shall be determined by the claims. Nevertheless, the description and drawings shall be used to interpret the claims". It is argued by the proponents of the description amendment requirement that, if the description is to be used to interpret the claims, the claims can only clearly define the invention if they are not contradicted by the description (T 1024/18 and T 2766/17). 

According to a second body of recent case law however, it is the claims that define the matter for which protection is sought (Article 84 EPC). As such, adaptation of the description is unnecessary because the claims by themselves should clearly define the invention without reference to the description ( T 1989/18, T 1444/20, and T 2194/19).

Amendment of the description post-grant

According to Rule 80 EPC, the description may also be amended post-grant "provided that the amendments are occasioned by a ground for opposition [...], even if that ground has not been invoked by the opponent". However, the EPC is silent on whether it is necessary to amend the description post-grant in order to align the description with post-grant claim amendments. 

Whilst recent case law on adaptation of the description predominantly relates to pre-grant amendments, a notable exception was the decision in T 1024/18. In this case, the Boards of Appeal rejected an Auxiliary Request filed by the Patentee solely on the grounds that the Patentee had not filed a copy of the description amended in line with the claims (IPKat). 

When and when not to amend the description post-grant (T 2391/18)

The decision in T 2391/18 related to the decision of the Opposition Division to maintain EP 1872074 as granted. The patent related to equipment for processing scrap metal. During appeal the Patentee filed amended claims and an adapted description. Amended claim 1 specified:

"Equipment for measurement and control of load material and scrap metal [...], said equipment comprising [...] a weighing device [...] wherein the weighing device [...] is coupled with a furnace shell support structure"

The description was amended by the Patentee to remove the words "in particular" from paragraph [0017], so as to bring the description in line with the amended claims:

"In particular, the weighing device [...] provides for a support structure for the furnace shell composed of support rollers."

The description was also amended elsewhere to remove the word "preferably".  

The Opponent argued that further amendment of the description was required in order to bring the claims in line with the description. Particularly, the Opponent argued, the description was broader than the amended claims because it specified merely that the weighing device "provides for a support structure", whereas claim 1 specified "a weighing device coupled with a support structure".

However, the inconstancy between the claims and the description was unarguably present in the granted claims before amendment. Particularly, the amended feature of claim 1 corresponded to the subject matter of dependent claim 2 as granted. Nonetheless, the Opponent argued that amendment of the description to bring it in line with the claims was as relevant post-grant as it was pre-grant (Article 84 EPC).

The Board of Appeal in the case disagreed that further adaptation of the description was required. First, the Board of Appeal noted that amendments in Opposition should be occasioned by a ground of Opposition (Rule 80 EPC). A lack of clarity under Article 84 EPC is not a ground for Opposition, except in cases where the lack of clarity arises solely as a result of a post-grant amendment (G 3/14). As such, the Board of Appeal was unequivocal that adaption of the description in opposition was not appropriate unless a new discrepancy between the description and the claims had arisen as a result of a post-grant amendment. 

Final thoughts

The decision in T 2391/18 provides some comfort for applicants and patentees with regards the controversial issue of description amendments. T 2391/18 particularly confirms that a granted patent cannot be invalidated solely on the grounds that the claims are unclear because the description was not adequately adapted before grant (Article 84 EPC). However, T 2391/18 also reaffirms the position of previous decisions requiring post-grant amendment in line with a claim amendment when a new discrepancy is introduced between the description and claims. As such, it would appear that any amended claims submitted during opposition that include limitations not present in the granted claims should always be accompanied by a corresponding amended description. 

Further reading 

• Board of Appeal finds no legal basis for the requirement to amend the description in line with the claims (T1989/18) (26 Dec 2021)
• Can amending the description to summarize the prior art add matter to the patent application as filed? (T 0471/20) (5 Jan 2022)
• Changes in the draft 2022 EPO Guidelines for Examination on description amendments: Substantial changes or window-dressing? (7 Feb 2022)
• EPO Board of Appeal toes the party-line on description amendments (T 1024/18) (4 April 2022)
• EPO workshop to provide users with "more certainty" on description amendments (25 May 2022)
• EPO: "EPO practice confirmed on adaptation of description" (19 July 2022)
• Board of Appeal case law against the description amendment requirement starts to mount up (T 2194/19) (16 Nov 2022)