How do I know what percentage I can claim?

This is entirely dependent on your agreements. Screenrights cannot provide advice or instruct you on what percentage you can claim.  We have prepared some sample contract clauses here that may help you determine what percentage you can claim.

The clauses and information contained on the linked page above are provided only for the purposes of highlighting relevant legal considerations. They should not be relied on as a substitute for legal advice. Before acting on any matter, you should obtain legal advice from a qualified legal practitioner.