by the United States House of Representatives, Copyright Law Revision (House Report No… (1976)
“ On the other hand, endowing a copyright claimant who has obtained a certificate with a rebuttable presumption of the validity of the copyright does not deprive the defendant in an infringement suit of any rights; it merely orders the burdens of proof. The plaintiff should not ordinarily be forced in the first instance to prove all of the multitude of facts that underline the validity of the copyright unless the defendant, by effectively challenging them, shifts the burden of doing so to the plaintiff. ”
