EPO case law: Essentiality test abolished

The essentiality test developed in decision T 331/87 on the question of whether the subject matter of the claim extends beyond the content of the application as originally filed when replacing or deleting a claim feature (which test has also been included into the Guidelines for Examination in the EPO) should no longer be used. Rather, the answer to this question must be based exclusively on the test referred to in decision G 2/10 as the "gold standard", i. e. whether the skilled person, using common technical knowledge, would consider the claimed subject matter to be disclosed – either explicitly or implicitly - directly and unambiguously in the application as originally filed. The fact that the Guidelines for Examination in the EPO prescribe the essentiality test is not decisive, since the BoA are not bound by the guidelines (EPO BoA 31 January 2017, T 1852/13).