If PBS and its stations, NPR and its stations, or other public broadcasting entity is not aware of the identity of, or unable to locate, a copyright owner who is entitled to receive a royalty payment under this part, they shall retain the required fee in a segregated trust account for a period of three years from the date of the required payment. No claim to such royalty fees shall be valid after the expiration of the three-year period. Public broadcasting entities may establish a joint trust fund for the purposes of this section. Public broadcasting entities shall make available to the Copyright Royalty Judges, upon request, information concerning fees deposited in trust funds.
37 C.F.R. §381.9