ID & Password Uniqueness—11​.300 (a)

"(a) Maintaining the uniqueness of each combined identification code and password, such that no two individuals have the same combination of identification code and password."

This requirement is most likely addressed by the procedures required for electronic signature uniqueness in 21 CFR 11.100(a).

One possible additional consideration is that rules for password components can be used to make passwords more difficult to guess. For example, password length of 6 or more characters, at least one capital letter, at least one letter and one number, would all contribute to making it more difficult to guess another's password.