T 1239/03 - and G 1/25

Key points

• In the run-up to the hearing on pending referral G 1/25 (hearing this Friday, 8 May, live stream link can be found here), the EBA issued a preliminary opinion on 11.03.2026 (indicating its intention to confirm the current practice of requiring description amendments) and invited the parties to comment by 17.04.2026. Several TPO's were filed by that date. One (anonymous) TPO drew attention to decision T 1293/03 (which was published on 02.01.2007).
• In that case, the proprietor deleted two examples from the patent during the oral proceedings before the |OD, seemingly by way of voluntary amendment. For the examination of whether this amendment complied with Art. 123(2), the Board considered it to be relevant that there was an ambiguity in the claims as granted. The Board reasoned that the skilled person would have to consult the description to establish the correct interpretation of the claim (i.e., in effect the same as under the current case law based on G 1/24). The Board also held that the two deleted examples were relevant in that context and that the skilled person would likely adopt a particular interpretation of the claim based on the information contained in those examples (which was, perhaps, precisely the reason why the proprietor wished to delete those examples). Therefore, the amendment deleting those examples was held to contravene Art. 123(2) EPC.
• Turning to the pending referral G 1/25, the EBA's preliminary opinion is to confirm the current practice that when the claims are limited, the description must be amended to conform. Suppose the EBA maintains this view in their final decision, it remains to be seen if this practice follows directly from the Articles of the EPC, or is of a more administrative nature such that the Administrative Council is competent to regulate the matter in the Implementing Regulations, and if the EBA in their decision gives a view on this point or leaves it open (disclosure: I submitted an amicus brief [link fixed] in which I discussed that Rule 48(1)(c) EPC is the pertinent provision).
• Perhaps the decision in case G 1/25 will not (and should not) be the last word on the balancing of the factors of quality (in terms of consistency), efficiency, and risks (under Article 123(2)/(3) EPC) that description amendments involve. 
• In the end, any rule under the EPC is legitimised not by being cast in stone but by being open to legislative debate and democratic political decision-making by the competent body - either the AC or a Diplomatic Conference.

  

Summary of the case

• The proprietor filed an auxiliary request wherein Examples 2 and 3 were deleted from the description. The OD decides to maintain the patent in amended form based on that auxiliary request. The opponent appeals.
• "[The opponent] argued that the deletions from the specification of the patent in suit carried out by the Patent Proprietor in the opposition proceedings, in particular the deletion of Examples 2 and 3 of the patent in suit, would have changed the meaning of Claim 1 which amounted to an extension of the patent in suit beyond the content of the application as filed and would, therefore, contravene Article 123(2) EPC, "
• "In view of the above arguments, statements and findings, the Board takes the view that (i), in order to understand the disclosure and teaching of the patent in suit, it has been necessary for the skilled reader to interpret the percentage range of the ethylene content in the elastomeric copolymer as defined in Claim 1 on the basis of the description, the general part of which was not, however, helpful in this respect, and, therefore more particularly, on the basis of the examples presented in the application as originally filed as describing preferred embodiments (page 12, line 16). He would have derived, namely from the disclosure in those Examples 1 and 3, that the patent application as filed lent a certain preponderance to interpreting the percentage value given for the ethylene content of component (b) as mol percent rather than weight percent, in particular since Example 3 did not comply with the interpretation of the percentage as being related to the weight (section VIII (4), above).
• "In addition to its explicit statement to this end (sections II (2) and VIII (3), above), the Respondent/Patent Proprietor has tried, by deleting Example 3 in particular, to give preponderance to an interpretation of the percentage value as weight percent. Although neither of the two interpretations can be made with certainty - be it before or after the amendment - there is a shift in the way the claim might be interpreted. Prior to the amendment, there was a preponderance for the interpretation "mol percent" (cf. sections VIII and 3.2.3, above) which due to the deletion of Example 3 has shifted towards "weight percent"."
• "In the Board's view, Article 123(2) EPC must be interpreted as referring to the patent (or application) as a whole rather than to the claims only. This finding proceeds directly from the clear wording of the Article. Hence, it is not crucial in which part of the patent (or application) an amendment has been carried out, but only whether the overall change in the content of the patent (or application) results in the skilled person being presented with information which is not clearly and unambiguously presented in the originally filed application, even when account is taken of matter which is implicit to a person skilled in the art."
• "It is clear, however, that the Patent Proprietor by deleting Examples 2 and 3 intended to have the percentage of ethylene content interpreted as weight percent. In such a case where it is certain that a shift in the interpretation of the claims has occurred, but uncertain if this would lead to an addition of subject-matter, the Board takes the view that it should be incumbent upon the Patent Proprietor or Applicant as the author of such amendment(s) to demonstrate that by making the amendment(s), the conditions of Article 123(2) EPC have been complied with."
•  "In the case at issue, the Patent Proprietor was, however, unable to demonstrate that before and after the amendments, the percentage value could have been consistently interpreted as "weight percent". Therefore, it must be concluded that the author of the amendments in the patent in suit, ie the Respondent, has not discharged the burden of proof which was on him."
• "the deletion of those two examples in order to exclude the possibility of interpreting the relevant percentage as mol percent provides a lateral shift of information corresponding to the extension of subject-matter beyond the content of the application as filed (Article 123(2) EPC). [...] it clearly shifts the gist of the patent in suit as defined in any one of Claims 1 to 13 [...], despite the fact that their wording has not been modified in this respect. In other words, the deletion of Example 2 and, in particular, of Example 3 amounts to the provision of an aliud."
• The proprietor was the respondent, and no auxiliary request was filed in the appeal that re-instated the two examples. The patent was revoked. 

EPO 

The link to the decision is provided after the jump.

https://www.epo.org/en/boards-of-appeal/decisions/t031239eu1

Attachment of TPO's citing the case: 

https://register.epo.org/application?documentId=MNITWUBP1024UX7&number=EP07704142&lng=en&npl=true