Good point. I'm not familiar with the American copyright law, but you're right, nowadays in most countries even if a piece of art is sold to another person, the artist still holds the copyright (the right to make copies) unless copyright transfer is specified in the contract.
But another way to look at this is, if the artwork is commissioned by the company for commercial purpose - much like if someone is commissioned to create a logo for a company - then the copyright is generally transferred to the company.
In the absence of a written contract, one can argue both ways, which I think is why the lawyers didn't think there was a strong case.
But another way to look at this is, if the artwork is commissioned by the company for commercial purpose - much like if someone is commissioned to create a logo for a company - then the copyright is generally transferred to the company.
In the absence of a written contract, one can argue both ways, which I think is why the lawyers didn't think there was a strong case.