Assessment of an Art. 53(a) EPC objection was to be made as of the filing or priority date of the patent or application in suit. Evidence arising thereafter might be taken into account provided it was directed to the position at that date (T 315/03).
Source: http://www.epo.org/law-practice/legal-texts/html/caselaw/2019/e/clr_i_b_2_2_1.htm
Date retrieved: 17 May 2021