Is it required by 13485, MDR that the design master file (or similar naming) has to have control numbers, revision, and signoff, or is a date and sign off on the document sufficient. I will be thankfull for any help.
There is no direct requirement that the design master file must have control numbers, revision, and similar. However, in ISO 13485:2016 in requirement 4.2.4 Control of documents is stated that all documents required by the quality management system must be controlled; and that that control includes the following: review and approve documents for adequacy prior the use; ensure that current revision status of and changes to documents are identified; prevent deterioration or loss of documents, and prevent the unintended use of obsolete documents and apply suitable identification to them.
Since the Desing master file is part of the quality management system, then this also applies to that file.
For more information what are common mistakes with ISO 13485:2016 documentation control and how to avoid them, please see the following link: