In reply to Form 405, applicants may pay some or all of the additional fees under protest. If they do so, then this triggers the protest procedure for determining whether the request for payment of the additional fees was justified (see also GL/PCT‑EPO C‑V, 5).[Rule 68.3(c); (e); GL/ISPE 10.78; ]
Source: http://www.epo.org/law-practice/legal-texts/html/guidelinespct/e/c_v_4_3.htm
Date retrieved: 17 May 2021