This is a tricky question … films are under the Berne Convention regarded as collective works. Article 14bis states that “Ownership of copyright in a cinematographic work shall be a matter for legislation in the country where protection is claimed.” So essentially a screen writer has a different status, depending on the country. In France, principal director and screen writer are considered to be the copyright holders of a film, in the UK it is the producer and the principal director. Similarly, in the Netherlands, it is assumed that all contributors to a film transfer their rights to the producer if there are no other contractual agreements. In the US you will most probably “work-for-hire”, i.e. hold no rights whatsoever. For details see the article Lights, Camera, Action! Directors’ Rights in Focus on CISAC’s website. Cineuropa is certainly also in a position to give legal advice.

Now to bargaining — or how to get most out of your rights as a script author. There are several points you could address: Obviously you could try to choose the country where your film would be made. Or you could try to negotiate a license of your rights to the producer (or whoever the copyright owner is), rather than a transfer. A license is typically limited to a certain period of time or for certain types of exploitation. Finally you could aim to become a producer of all the films that use your scripts to make sure you’re in the position of the copyright holder.

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These are the soucres I used to compile this answer:
- http://www.wipo.int/treaties/en/ip/berne/trtdocs_wo001.html
- http://www.cisac.org/web%5Ccontent.nsf/Builder?ReadForm&Page=Article&Lang=EN&Alias=web-2005-directorsrights
- http://www.cineuropa.org/
- http://www.netwerkscenario.nl/
- http://www.auteursrecht.nl/auteursrecht/pagina.asp?pagkey=22248
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The position in the UK is that we have the PACT/Writers’ Guild agreement (currently in urgent need of updating). This gives a minimum terms baseline for writers or their agents to negotiate up from. The fact is though (as Peter has stated) that the producer usually takes ownership of the script and the writer is “asked” to waive their moral rights; refusal to do so usually means no deal!