There was some US case law quoted here where the court decided the contractors owned the copyright, and the client only had a (very broad) license. That said,

There was some US case law quoted here where the court decided the contractors owned the copyright, and the client only had a (very broad) license. That said, it's smart to explicitly write it in the contract; I believe a typical formulation is that the developer owns the copyright until payment, when it transfers to the client.