area291 wrote:
In actuality that isn't very smart.  Co-owners of copyright have a legal status known as "tenants in common."  This is similar to home or property ownership where if two people own a house as "joint tenants," then, when one of them dies, the other person will automatically become owner of the whole house.  The same principles can apply if the copyright sharing documents are not drafted properly, or worse if not drafted at all and only verbalized.  Hardly an expense worthwhile for models and photographers for uncommissioned imaging without high value.

Actually, I was aware of the tenants in common (which is caused by joint authorship). However, I believe that you are incorrect in your definition of it. Tenancy in common in contract law each party holds a % of the rights to a specific piece of work, with equal rights (unless mentioned in the contract) to do with it as they wish. Their interest in the work is assignable and transferable. They can leave their % of interest to another in their wills or it will be transferred to their decendents upon death.

The one that you are describing is joint tenancy which is a different ballgame.

Joint Tenants, Tenants in Common and Tenants in Entirety are three completely separate legal terms each with their own pluses and minuses.