An additional search will sometimes be required either at the first stage of amendment or subsequently. This may arise for a number of reasons (for more details, see Guidelines C‑IV, 7.2 – November 2018 version).
Source: http://www.epo.org/law-practice/legal-texts/html/caselaw/2019/e/clr_iv_b_4.htm
Date retrieved: 17 May 2021