On October 17, 2016, a Technical Board of Appeal has referred fundamental questions of law concerning the allowability of undisclosed disclaimers in a patent claim to the Enlarged Board of Appeal (T 0437/14). The case law of the Enlarged Board of Appeal has made a distinction between “disclosed disclaimers” and “undisclosed disclaimers” (G 1/03 and G 2/03). Regarding disclosed disclaimers, it has been said: “The test to be applied is whether the skilled person would, using common general knowledge, regard the remaining claimed subject-matter as explicitly or implicitly, but directly and unambiguously, disclosed in the application as filed”. However, the Enlarged Board of Appeal has expressed in G 1/03 regarding undisclosed disclaimers: “An amendment to a claim by the introduction of a disclaimer may not be refused under Article 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”. Arguably, the Enlarged Board of Appeal gave up its more generous approach regarding undisclosed disclaimers in its decision G 2/10 by saying: ”The overriding principle for any amendment to be allowable under Article 123(2) EPC is that the subject-matter of an amended claim must be at least implicitly disclosed to the skilled person, using common general knowledge, in the application as filed. As has also been set out in the foregoing, that applies equally to the subject-matter of a claim the scope of which is determined by a disclaimer”. The Technical Board of Appeal now came to the conclusion that the case law of the Appeal Boards is not consistent and that the Enlarged Board of Appeal should clarify whether or not there is only one standard applicable to all kinds of disclaimers.