Regarding the drafting of disclaimers, the Enlarged Board of Appeal stated in G 1/03 and G 2/03 (OJ 2004, 413 and 448) and confirmed in G 1/16 (OJ 2018, A70) that the disclaimer should not remove more than was necessary to restore novelty or to disclaim subject-matter excluded from patentability for non-technical reasons. The need for a disclaimer was not an opportunity for the applicant to reshape his claims arbitrarily. In G 2/10 (OJ 2012, 396) the Enlarged Board held that the requirement that "the disclaimer should not remove more than is necessary to restore novelty" was not suitable for the disclaiming of disclosed subject-matter, since in that case the wording of the disclaimer must be configured in accordance with the disclosure of the disclaimed subject-matter in the application as filed.

As to the relationship between the requirement that "the disclaimer should not remove more than is necessary to restore novelty" and the requirement of clarity and conciseness, see T 2130/11 (summarised in chapter II.E.1.7.3 e) "Drafting of disclaimers – clarity" below).

In T 747/00 the board concluded that since, in the absence of a novelty-destroying disclosure in document (5), the disclaimer removed subject-matter without any need to do so, that disclaimer necessarily removed more than was necessary to restore novelty, which was not allowable (see also T 201/99). In T 1050/99 the board concluded that the disclaimer covered more than was disclosed in the prior art and thus removed from the claim more than was necessary to restore novelty. See also T 285/00 which concerned a disclaimer largely not based on the disclosure of a prior art document cited under Art. 54(3) EPC 1973, thereby rendering the remaining claimed subject-matter more distant from a relevant prior art document cited under Art. 54(2) EPC 1973.

In T 8/07 the board observed that G 1/03 had stated that a disclaimer may serve exclusively the purpose for which it is intended and nothing more. If a disclaimer had effects which went beyond its purpose, it was or became inadmissible. Further, the necessity for a disclaimer was not an opportunity for the applicant to reshape his claims arbitrarily (G 1/03, point 3 of the Reasons). Therefore the disclaimer should not remove more than was necessary to restore novelty or to disclaim subject-matter excluded from patentability for non-technical reasons. From that the board found that it could not be derived from the reasoning of G 1/03 that a patent proprietor was permitted a degree of discretion or latitude concerning the "border" within which the disclaimer should be drafted with respect to the subject-matter to be excised. On the contrary, the existence of any discretion regarding the extent of the disclaimer as compared to the subject-matter to be excluded would inevitably introduce a degree of arbitrariness in the drafting of the disclaimer. This would conflict with the express findings of G 1/03. It was therefore concluded that in order to comply with the requirements following from G 1/03 with respect to the drafting of disclaimers it was necessary that these be formulated to excise only that subject-matter which could not be claimed. Further, the submission of the patent proprietor that it would derive no advantage was not necessarily and inevitably correct since a broad disclaimer, in addition to restoring novelty would have the further effect of "immunising" the subject-matter claimed against a potential attack of lack of novelty.

In T 10/01 the scope of the disclaimer was broader than was necessary to restore novelty. The board nevertheless referred to point 3 of the Reasons for G 1/03, saying that it could also be inferred from that decision that a disclaimer that was broader than strictly necessary to restore novelty might be allowed, depending on the circumstances of the case, if that proved necessary to prevent any lack of clarity in the claim that might otherwise result. However, in the case at issue there was no apparent justification for the disclaimer being broader than the disclosure in document (1).

In T 477/09 claim 1 was modified by addition of a disclaimer with a view to restoring its novelty over document D1. It was undisputed that there was no basis for the disclaimer in the application as filed. The board observed that two conditions relating to the wording of disclaimers had been established in points 2.2 (disclaimer should not remove more than is necessary) and 2.4 (clarity and conciseness) of the Order made in G 1/03 and that those two conditions were equally applicable. The patent proprietor therefore could not be considered to have any room for manoeuvre in wording the disclaimer and thereby defining its scope: to satisfy the conditions set out in G 1/03, a disclaimer could not remove more than was necessary to restore novelty. In the case at hand, the board found that the scope of the disclaimer was greater than the actually novelty-destroying disclosure in D1.

In T 1843/09 (OJ 2013, 502) the opponent argued that the disclaimer contravened Art. 123(2) EPC because the wording of the disclaimer that the claimed film "is other than a film of Comparative Example 4 of EP-A 0546184" did not represent a technical feature. The board did not accept this argument. Although it was true that technical information could not directly be extracted from the wording of the disclaimer as such, it should be noted that the disclaimer did not merely cite a published patent document, but clearly referred to a specific disclosure in D15, namely a single film described in comparative example 4. Table 4 of D15 characterised this film unambiguously by a number of technical features. The skilled person was therefore able to determine simply by reading the comparative example in D15 which technical embodiment should be excluded from the scope of the claim.

In T 1836/10 the examination division had based its refusal of the application on Art. 53(a) in conjunction with R. 28(c) EPC. The applicant attempted to disclaim the relevant subject-matter. The board considered that an applicant could not amend his claims at will, and that any disclaimer needed should not exclude any more than was necessary to disclaim subject-matter excluded from patentability for non-technical reasons. The same applied to a disclaimer which served to disclaim subject-matter that was not comprised by the claim in the first place.

The board in T 1224/14 found that a disclaimer was no longer needed to restore novelty over the prior-art example 5A of D1 because the example had become irrelevant for novelty purposes following a limitation of the claimed subject-matter. The disclaimer thus removed more than was necessary to restore novelty and was therefore at odds with the decision in G 1/03.

In T 1354/15 the appellant had argued that, since the disclaimer at issue specified not merely the specific L-dsRNA sequence disclosed in D7, but also the C18 linker group between the two strands, it removed more than was necessary to restore novelty. In the board's view however, the RNA described in D7 was characterised also by the C18 linker. The fact that the application as filed did not contemplate such linkers did not result in the skilled person being presented with new technical information. Excluding the specific RNA having a C18 linker did not provide any technical contribution to the subject-matter disclosed in the application as filed.