The Certificate of Conformance (COC) is the final step in the Airworthiness process. The COC is released by a drone manufacturer upon being satisfied that the drone conforms to the certificate of manufacture and airworthiness. The manufacturer can then produce one or more drones of the same class and type. The COC is also a necessary document for listing your RPAS on Digital Sky. The COC can be issued in a format specified under form UA-4.