No, there's nothing official about the Linux kernel implementation. Though you could make the case for BSD... That aside, the reason it makes you a bad citize

No, there's nothing official about the Linux kernel implementation. Though you could make the case for BSD... That aside, the reason it makes you a bad citizen is the lack of follow through. If you're a small organization writing a network implementation, you know from the start that your implementation is unlikely to get the decade+ of follow-through that is necessary to fix your interoperability problems. Instead you're putting that cost on every other internet host that is going to have to interact with your out-of-spec implementation until the day the last instance of your code is shut down.