If any document other than those making up the application (e.g. a letter from the applicant in reply to an invitation under Art. 94(3)) is not filed in one of the prescribed languages or, where the applicant avails himself of Art. 14(4), the required translation is not filed in due time, it is deemed not to have been received. The person who has filed the document must be notified accordingly by the EPO. Accompanying documents relating to performance of a procedural act subject to a time limit (e.g. filing the designation of the inventor, the certified copy of the earlier application for which priority is claimed or that application's translation under Rule 53(3) into one of the official languages of the EPO) are dealt with as follows: if the European application number is given, the document goes into the dossier and the procedural act is recognised as having been performed, but any other contents are ignored. Regarding the signature of accompanying documents, see A-VIII, 3.1.
According to Art. 115, following the publication of the European patent application, any person may file observations in writing concerning the patentability of the invention in respect of which the application has been filed. These written observations must be filed in English, French or German. Otherwise, they are deemed not to have been received.
Even though deemed not to have been received, the document not filed in the prescribed language will become part of the file and therefore accessible to the public according to Art. 128(4). Observations by third parties and notices of oppositions will be communicated to the applicant or the patent proprietor, respectively, even if they have not been filed in the prescribed language and are therefore deemed not to have been filed (see Art. 14(4) and Rule 3(1) regarding the notice of opposition or Art. 14(4) and Rule 114(1) regarding third party observations) (see D-IV, 1.2.1 (v) regarding the legal consequences where a notice of opposition or notice of intervention of the assumed infringer is filed in a non-prescribed language).