I wrote a contract in 2016 that can be used to transfer one’s artwork to another person or legal entity. It means that the original maker or thinker of the artwork can assign full copyright, physical ownership, intellectual property and moral rights of the artwork to the signatory permanently. Both entities agree to keep the agreement secret. Moreover, they act publicly as if the artwork was, is and will be the exlusive creation of the signatory.

You can download, use and modify the contract here:

Agreement on the Assignment of a Work of Art
Entente sur la cession d’une oeuvre d’art (French Version)