If the file number of the previous application under Rule 52, paragraph 1, or the copy of that application under Rule 53, paragraph 1, have not been filed in due time, the European Patent Office shall inform the applicant accordingly and invite him to file them within a period to be specified.
Source: http://www.epo.org/law-practice/legal-texts/html/epc/2016/e/r59.html
Date retrieved: 17 May 2021