I taught at a German university for a few years. And they way grades were handled was, you had to print a standardized piece of paper for every student with their name, date of examination, and grade, and drop them off at the secretary's office.
The secretary would stamp every such Schein with a rubber stamp. Then the students would pick up their Scheine at the secretary's office and bring it to the examination department themselves (!) to get the grade registered. Only at the very of my time there, they changed the system and I could hand in the grades directly to the examination department.
At any rate, the system was so stupid. It was trivial for students to print a new Schein with a better grade and register that (there must have been a lot of fraud). But the counter argument was 'no, it's very safe because the students do not have a rubber stamp'. Of course, the rubber stamp was just the university logo with something like the faculty name next to it. Trivial to copy (or make a rubber stamp for more enterprising students).
Probably the procedure had been followed since 1573, well before home printers, scanners, phone cameras, or get-your-own-rubber-stamp-for-a-few-bucks internet shops.