“Forced Exquisite Corpse” another term for a collage piece done by many different artist, but without their consent. I just added the word “forced” in front to imply that when doing collage you are not allowing the artist to choose but rather force his hand by using reproductions of the artist own work.

“Exquisite Copse is a method by which a collection of words or images is collectively assembled. Each collaborator adds to a composition in sequence, either by following a rule (e.g. “The adjective noun adverb verb the adjective noun”) or by being allowed to see the end of what the previous person contributed.”
– www.en.wikipedia.org/wiki/Exquisite_corpse

This detail of the collage below is a classic example of “Forced Exquisite Corpse”.  The images were found in ARTnews magazines instead of being offered up by the artist.

Forced Exquisite Corpse Collage by Sam Roloff Artist Portland Oregon 201