2. What are the requirements governing the serial number (SN)?

The serial number has to comply with Article 4(b)(ii) of the Delegated Acts. A serial number is a numeric or alphanumeric sequence containing the maximum of 20 characters generated by a deterministic or nondeterministic randomisation algorithm. The probability that the serial number can be guessed must be negligible and less than 1:10 000 (as per Article 4(c) of the Delegated Acts).