Language of further correspondence
Any other correspondence with the EPO as IPEA may be in any of the EPO's three official languages with the exception of amendments to the application, which are to be filed in the same language as the demand (see point 4.1.043).
Source: http://www.epo.org/applying/international/guide-for-applicants/html/e/ga_c4_1_12_2.html
Date retrieved: 17 May 2021