I have a customer who purchased some URD cable. The neutral does NOT have a stripe of any sort. The 3 legs are are identified by the print legend. i.e.. "Phase A", "Phase B" and "Neutral" are printed on their respective legs. Black cable, White print. They are clearly marked by the white print legend. Is this acceptable means of identification? Is there any National Electric Code for color identification specifically to URD cable?

I believe the cable is marked correctly. I'll look at my code book later on and verify it for you.

Generally, the NEC specs are geared toward the size of the cable, not type specific.

The sizes are 6 AWG and smaller and 4 AWG and larger. For the record, neither grouping calls for the naming of the conductors. Identification for the grounded conductor is either a gray or white outer finish or three white strips along the outer shell. Also at the termination of the wire, a white marking is allowed.

Find out if this cable is UL or CSE listed...
If it is, then it is permitted for use as allowed by the NEC.