I'm not sure what you're saying. I think you're saying that an author [you?] assigned his copyright to someone who then applied to register the copyright and, on the registration form, indicated it was the copyright claimant by virtue of a written agreement with the author -- but that, in fact, there was no written agreement with the author. If those are the facts then PERHAPS the copyright registration can be invalidated. It does NOT automatically follow from that outcome, however, that the author regains ownership of the copyright. Whether the assignment of the copyright from author to buyer is valid or not depends on many facts that you have not yet shared -- and which you should not share in public.
Big picture: The copyright in a work exists independant of and regardless of whether the copyright is registered with the Copyright Office. Someone owns the copyright. Who does is not dependant on what's asserted on the registration form. You need to speak with your own copyright attorney in private to figure out if the purported assignment of the copyright from author to buyer is valid. In nearly all circumstances a written agreement is required.
The above is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
The question isn't very clear, but Mr. Ballard's point that copyright ownership is not the same thing as being the person who registered the copyright with the copyright office, is well taken.
The author is a Maryland attorney; however no answer given on Avvo is intended as legal advice or intended to create an attorney-client relationship. Dan's expertise lies in the electronic entertainment (video game) industry, as well as complex internet law issues, electronic free speech, entertainment law, copyright and trademark law, and computer fraud. He primarily represents game developers and founders of emergent internet technologies.
Mr. Ballard's response seems most appropriate.
The key issue is first to make sure that the ownership of the material is clearly understood. This question can be answered without regards to the registration. Then assuming nothing changed in the ownership you may or may not want to address the registration issue.
But to the heart of your concern I agree with counsel that this would not affect the actual ownership of the copyright here.
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