The definitive source for a correct PID regexp is probably the BBC themselves, and it just so happens that they provide one: https://github.com/bbc/programmes-pages-service/blob/master/src/Domain/ValueObject/Pid.php#l14 ^[0-9b-df-hj-np-tv-z]{8,}$ HTH. -- James Scholes http://twitter.com/JamesScholes