More than one author creates a copyrightable work. Each author becomes a co-owner and is treated under the law as “tenant in common” each having an independent and equal right and ownership and legal rights in the entire property or work. Thus each possesses the right to license, sell and use of a work.
Joint Work:
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.