The photo-law around copyright is somehow funny think, and tricky. In Canada it works just around commissioned work, that is, just for negatives that are made as part of commissioned work. Who can prove some specific negative is a part of commissioned work? And what is 100% accurate definition of commissioned work?
Photog always can say: I gave to the commissioner negatives, and this particular negative is not part of our contract. I sold (or presented if tax is in play) him the photograph separately so it is how come he has a photograph of that negative. If some work is contracted so accurate and leave no room to photographer, just give up, not end of life. Contracts that can run photographer into trouble about ownership of negatives are so rare, next to none, even in Canada.
By the way, most of commercial commissioned works today (at least in Canada) are done by computer so who care to whom negatives belong. Copyright in such medium is so funny think to me (not to say stupid), and I am not sure it exists at all.
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