Maybe that's a UK thing, but in the states, many presses--the big commercial kind--own the copyright. Some of them don't even pay royalties. They pay one-time up front fees.

I know of National Book Award winning writers who have written books that have not been published at all by publishers, and the writers can't get the books back to sell them elsewhere. Once a book is purchased in the states, the copyright is typically held by the publisher unless the writer has retained it.