CUSIP Installation composer require dprmc/cusip Usage use \DPRMC\CUSIP; $isCusip = CUSIP::isCUSIP('notacusip'); // false $isCusip = CUSIP::isCUSIP('222386AA2'); // true Notes A PHP (v5.6+) library for validating CUSIP codes. And in case you were wondering what a CUSIP was: https://en.wikipedia.org/wiki/CUSIP
