In Europe, amendments of patent applications and patents before the European Patent Office (EPO) are governed by Article 123 of the European Patent Convention (Article 123 EPC). In particular, Article 123(2) EPC states that a European patent application or European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.
Claim amendments may involve the introduction of a disclaimer, i.e. words identifying subject-matter that is not claimed. A disclaimer may also involve the introduction of a negative limitation in an existing claim, i.e. "an amendment to a claim resulting in the incorporation of a 'negative' technical feature therein, typically excluding from a general feature specific embodiments or areas". A disclaimer lacking basis in the application as filed is called an undisclosed disclaimer. A disclaimer having a basis in the application as filed, e.g. in the form of an embodiment, is called a disclosed disclaimer.
In decisions G 1/03 and G 2/03 (hereinafter G 1/03) the Enlarged Board of Appeal (EBA) of the EPO clarified the criteria that must be fulfilled for a claim amendment involving an undisclosed disclaimer to comply with Article 123(2) EPC. These criteria are restoration over earlier filed but later published prior art, accidental anticipations (e.g. prior art from an unrelated technical field), or disclaiming subject-matter which is excluded for non-technical reasons. More detailed information about the criteria is provided below.
Regarding claim amendments involving a disclosed disclaimer, decision G 2/10 states that compliance with Article 123(2) EPC should be examined using the so-called gold standard disclosure test. In this test, it is assessed if the amended subject-matter is directly and unambiguously derivable from the application as filed. However, decision G 2/10 also suggests the use of the gold standard disclosure test for claim amendments involving undisclosed disclaimers.
In the case which was referred to the EBA by the Technical Board of Appeal as G 1/16, claim 1 of the Main Request had been amended by the introduction of two undisclosed disclaimers, the allowability of which hinged on the application of the aforementioned decisions.
The EBA of the EPO has now issued its decision in G 1/16 in which it is established that a claim amended by the introduction of an undisclosed disclaimer is allowable under Article 123(2) EPC provided that it fulfills one of the criteria set out in G 1/03. Further, the introduction of the undisclosed disclaimer may not provide a technical contribution to the subject-matter disclosed in the application as filed, may not be relevant for the assessment of inventive step or sufficiency of disclosure, and may not remove more subject matter than necessary to restore novelty or to disclaim subject-matter excluded from patentability for non-technical reasons.
In its decision, the EBA also clarifies that the gold standard disclosure test referred to in decision G 2/10 is not the relevant test for examining whether a claim amendment by an undisclosed disclaimer complies with the requirements of Article 123(2) EPC.