§ 204. Execution of transfers of copyright ownership
(a)
A transfer of copyright ownership, other than by operation of law, is not valid unless an instrument of conveyance, or a note or memorandum of the transfer, is in writing and signed by the owner of the rights conveyed or such owner’s duly authorized agent.
(b)
A certificate of acknowledgement is not required for the validity of a transfer, but is prima facie evidence of the execution of the transfer if—