Joint authorship

Joint authorship of a copyrightable work is when two or more persons contribute enough to the work to be the author of that work. In the case of joint authorship, the authors share the copyright in the work with each other.

Article 7bis of the Berne Convention states the term of protection for works of joint authorship and extends the general terms of protection provided under Article 7 to works of joint authorship, under the condition that the term of copyright protection must be measured from the death of the last surviving author. But the Berne Convention doesn’t define what works of joint authorship are, because various national legislations have a lot of variations while defining the same, and have a different approach to the topic.

This problem relating to joint authorship is not specifically dealt with by other international agreements as well, like the UCC, TRIPS, and the WIPO Copyright Treaty 1996.

A joint work is defined in Section 101 of the U.S. Copyright Act as “a work prepared by two or more authors with the intention that their contributions be merged into inseparable or interdependent parts of a unitary whole."Section 201(a) gives the status of co-ownership in the copyrighted work to such authors of a joint work.

Under the US copyright law, a person has to prove the following two things for claiming joint authorship in a work:

The individual contributions made by authors to a joint work need not necessarily be equal in quality or quantity. Nevertheless, the author has to show that his contribution to the joint work is copyrightable by itself. A contribution of mere ideas is not sufficient. In order to be a joint author, one must contribute expression. For the expression to be copyrightable it has to be original – that is independently created and possess at least a minimal degree of creativity.

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Wikipedia