There is no obligation to file a confirmation copy of subsequent documents filed by fax, but the EPO as receiving Office may require one to be submitted and will do so in particular if the applicant has submitted substitute sheets under Rule 26 PCT
and/or any sheets to be incorporated by reference under Rule 20.6 PCT
. In these cases, applicants are advised to submit a confirmation copy on their own initiative directly after sending the sheets concerned by fax (see point 2.2.025
). If a confirmation copy is not submitted within the time limit prescribed in the invitation issued by the EPO as receiving Office, the document will be treated as not having been received.