Refund of the search fee
If the supplementary European search report is based on an earlier search report drawn up by the EPO, or if the application claims the priority of a previous application for which a search was carried out by the EPO, (a part of) the fee paid for the supplementary European search may be refunded. The level of the refund depends on the type of earlier search and the extent to which the EPO benefits from the earlier search report when carrying out the supplementary European search.
Source: http://www.epo.org/applying/international/guide-for-applicants/html/e/ga_c5_9_4_3.html
Date retrieved: 17 May 2021