Previously, the Enlarged Board had dealt with the admissibility of a “disclaimer” in decisions G1/03 (G2/03) and G2/10. G1/03 established certain criteria for the admissibility of an “undisclosed disclaimer”, the second decision G2/10 was concerned with a different type of “disclaimer”, namely “disclosed disclaimer”. According to G1/03 “undisclosed disclaimer” are, for instance, essentially admissible to establish novelty over prior art under Article 54 (3) EPC or an accidental anticipation. According to G2/10 a disclaimer is essentially admissible if the subject matter remaining in the claim after introduction of the “disclaimer” is directly and unambiguously disclosed to the skilled person using common general knowledge in the application as filed. The standard set by decision G1/03 has been widely used by the departments of the first instance of the European Patent Office to assess the admissibility of an “undisclosed disclaimer”. However, diverging case law of the Technical Boards of Appeal following G2/10 with regard to the question which standard has to be applied to assess the admissibility of an “undisclosed disclaimer” - the standard of G1/03, the standard of G2/10, or both - has led to the referral to the Enlarged Board underlying the present decision G1/16. The Enlarged Board has now decided that only the test according to earlier decision G1/03 has to be applied to assess the admissibility of an “undisclosed disclaimer”. No additional “remaining subject matter” test, as formulated in decision G2/10, is required. This decision brings back legal certainty to patent applicants and truly simplifies the use of an “undisclosed disclaimer”. Proceedings that had been stayed in light of this referral to the Enlarged Board will likely be resumed shortly.