1.7.2 Standards for examining disclosed and undisclosed disclaimers
In the case law that followed these decisions of the Enlarged Board there was no uniformity of approach regarding the application of G 2/10 to "undisclosed disclaimers" (see CLB, 8th edn. 2016, II.E.1.5.2b) and the summary in G 1/16, point 24 of the Reasons). This led to the referring decision T 437/14 of 17 October 2016 date: 2016-10-17 (OJ 2017, A50) asking in particular whether the standard referred to in G 2/10 for the allowability of disclosed disclaimers under Art. 123(2) EPC, i.e. whether the skilled person would, using common general knowledge, regard the subject-matter remaining in the claim after the introduction of the disclaimer as explicitly or implicitly, but directly and unambiguously, disclosed in the application as filed, was also to be applied to claims containing undisclosed disclaimers.
In G 1/16 (OJ 2018, A70) the Enlarged Board considered that the choice of the proper test for assessing the allowability of any disclaimer is determined by the fundamental distinction, in terms of their legal nature, between disclosed disclaimers and undisclosed disclaimers. That distinction necessitates providing for each of the two classes of disclaimer a single specific test for assessing whether the introduction of a given disclaimer is in compliance with Art. 123(2) EPC. Therefore, for undisclosed disclaimers the proper test is whether the criteria of G 1/03 (OJ 2004, 413) are fulfilled, and for disclosed disclaimers the proper test is the "gold standard" disclosure test of G 2/10 (OJ 2012, 376).
The assessment of the allowability of a claim amendment by an undisclosed disclaimer is governed exclusively by the criteria laid down in G 1/03. No modifications are to be made to, nor any conditions added which go beyond, the criteria of G 1/03.
The Enlarged Board confirmed that an amendment by an undisclosed disclaimer may be allowable in the three situations mentioned in G 1/03 (point 2.1 of the Order), i.e. in order to (1) restore novelty by delimiting a claim against state of the art under Art. 54(3) EPC; (2) restore novelty by delimiting a claim against an accidental anticipation under Art. 54(2) EPC; or (3) disclaim subject-matter which, under Art. 52 to 57 EPC, is excluded from patentability for non-technical reasons.
In addition, the undisclosed disclaimer must not be related to the teaching of the invention, as already held in G 1/03 (point 2.3 of the Order; point 2.6 of the Reasons). In endorsing this concept, the Enlarged Board provided the following explanations:
The question to be asked in this context is not whether an undisclosed disclaimer quantitatively reduces the original technical teaching – this is inevitably the case – but rather whether it qualitatively changes it in the sense that the applicant's or patent proprietor's position with regard to other requirements for patentability is improved. If that is the case, then the original technical teaching has been changed by the introduction of the disclaimer in an unallowable way. And as a consequence, the technical teaching based on the amended claim, i.e. on the remaining subject-matter without the disclaimer, can no longer be considered as belonging to the invention as presented in the application as originally filed.
For the sake of completeness, the Enlarged Board added that the prohibition of a qualitative change in the original teaching applies in an absolute way, i.e. not only with regard to the prior art which provides the basis for the undisclosed disclaimer, but also to the entire prior art relevant for the assessment of inventive step. In practical terms, this means that the evaluation of inventive step has to be carried out disregarding the undisclosed disclaimer, as proposed in T 710/92. In this way, any unallowable modification of the original technical teaching in the assessment of inventive step is avoided.
The Enlarged Board concluded that the introduction of an undisclosed disclaimer must fulfil one of the criteria laid down in point 2.1 of the Order of decision G 1/03, but may not provide a technical contribution to the claimed subject-matter of the application as filed; in other words, the identity of the invention as originally filed must remain unchanged by the subject-matter remaining in the claim after the introduction of the undisclosed disclaimer.
The Enlarged Board answered the questions referred to it as follows:
For the purpose of considering whether a claim amended by the introduction of an undisclosed disclaimer is allowable under Art. 123(2) EPC, the disclaimer must fulfil one of the criteria set out in point 2.1 of the Order of decision G 1/03.
The introduction of such a disclaimer may not provide a technical contribution to the subject-matter disclosed in the application as filed. In particular, it may not be or become relevant for the assessment of inventive step or for the question of sufficiency of disclosure. The disclaimer may not remove more than necessary either to restore novelty or to disclaim subject-matter excluded from patentability for non-technical reasons.
- T 0518/22
In T 518/22 the board established that the "A3" mutant disclosed in D2 anticipated the subject-matter of claim 1 of auxiliary request 1 at least under Art. 54(3) EPC.
Claims 1 and 9 of auxiliary request 2 differed from the respective claims in auxiliary request 1 in that an undisclosed disclaimer had been introduced to exclude the A3 mutant disclosed in D2 from the subject-matter claimed.
The board explained that, according to G 1/03, an amendment to a claim by the introduction of a disclaimer may not be refused under Art. 123(2) EPC for the sole reason that neither the disclaimer nor the subject-matter excluded by it from the scope of the claim have a basis in the application as filed. G 1/03 defines the criteria when such an undisclosed disclaimer is allowable, stipulating that it can be introduced into a claim inter alia to restore novelty by delimiting a claim against the state of the art under Art. 54(3) EPC but not under Art. 54(2) EPC (except for a so-called accidental disclosure).
In order to determine whether D2 was prior art under Art. 54(2) or (3) EPC for the claimed subject-matter, the board assessed whether the subject-matter of claim 1 as a whole was entitled to claim priority from P and whether D2 was entitled to claim priority from P1.
The board found that D2's priority based on P1 was valid. Appellant I had objected to D2's formal entitlement to priority because the applicants of P1 and those of the international patent application D2 were not the same. The board explained that G 1/22 and G 2/22 established that a presumption exists that a claim to priority is valid by way of an implicit agreement on the transfer of the right to claim priority in the absence of evidence that such an agreement (implicit or explicit) did not exist. This presumption applies to any case where the subsequent applicant is not identical with the priority applicant. On account of this general teaching, the board understood that the presumption applied also to patent applications cited as prior art, as in the present case (see also T 521/18).
This presumption could be rebutted to take into account "rare exceptional cases" where the subsequent applicant could not justifiably rely on the priority (G 1/22). This, however, involved the reversal of the burden of proof, i.e. the party challenging the subsequent applicant’s priority entitlement (here appellant I) had to prove that this entitlement was missing. Merely raising speculative doubts was not sufficient. Instead, evidence was required that specific facts supported serious doubts about the subsequent applicant's entitlement to priority (G 1/22). In the absence of evidence suitable to establish that the alleged real priority right holder did not allow the subsequent applicant to rely on the priority (see also T 1975/19), appellant I's objection against D2's formal entitlement to priority from P1 was not sufficient to rebut the presumption of validity, which always existed on the date on which priority was claimed (G 1/22). Hence, D2 validly claimed priority from P1.
As regards the validity of the patent's priority claim based on P, the board established that the relevant date for the subject-matter of claim 1 in several embodiments concerning SEQ ID NOs: 5 to 8 was the filing date of the patent application, whereas several embodiments of claim 1 in relation to SEQ ID NO: 4 were entitled to claim partial priority from P (G 1/15).
Therefore, D2 was prior art under Art. 54(2) EPC for the subject-matter of claim 1 not enjoying priority, i.e. in relation to several embodiments concerning SEQ ID NOs: 5 to 8, and prior art under Art. 54(3) EPC for the subject-matter of claim 1 enjoying priority, i.e. in relation to several embodiments concerning SEQ ID NO: 4.
Since the undisclosed disclaimer added to claim 1 in auxiliary request 2 removed embodiments of D2 which belonged to the state of the art pursuant to Art. 54(2) EPC and were not an accidental disclosure, such amendment was not allowable under Art. 123(2) EPC. Auxiliary request 2 comprised added subject-matter (G 1/03 and G 1/16) and did not fulfil the requirements of Art. 123(2) EPC.