3. Derogations from the language of the proceedings in written proceedings
3.1 Written submissions
With the exception of amendments and corrections to the application, for which the language of the proceedings must be used, any other correspondence with the EPO can be in any of the EPO official languages.
The EPO as receiving Office will, however, reply in the language of the proceedings.
R. 92.2(b)
AI 104(a)
OJ EPO 1993, 540