"2. Ancillary Subscription Services
49. Radio stations may wish to offer certain digital audio or data
content under a subscription model. In this context, ancillary
subscription services may be available for a fee or the listener may
simply need to enter a code to access the service."

This is just to clear any doubt about the fact that pay radio is an option
in the IBOC plan.

Found at:

http://a257.g.akamaitech.net/7/257/2...7/E7-15922.htm

Frank Dresser