Originally Posted by Kyrpto
Not sure if this belongs here but how does copyright work when you're collaborating with a singer/songwriter or other artists? Are the copyrights automatically split evenly? Let's suppose I want to sample my song that I worked on with another artist. But the part I'm sampling was written by the other artist. Would that be a problem?
Yes, the copyrights are by default split 50/50 under what's called a Shared or Joint Copyright which is established at the time of creation provided no other agreement is in place. That can be altered by formal legal paperwork (Assignment/Transfer of Copyright). To be completely in the right you'd need at least written use permission to do anything with it (remix, etc). That way there's a way to determine royalties off the new product.
If you hire someone to write music or lyrics for you and pay them, you then own those lyrics provided you have documentation that you paid for them (usually called Work for Hire). That's the same as if you wrote a piece of software while working at a company - the company paid you for your time, they own the code.
All that said, people take this shit to lawyers and court all the time and it always comes down to who has the better or more convincing paper trail. Copyright is a massive grey area. It's not like there's just magic rules that sort everything out, especially when it comes to more than one person creating a single work.
It's probably also worth looking up mechanical vs performance vs sync licenses and copyrights, as what you're doing with a piece of work determines what kind of license you need and who owns the copyright (like you can own the copyright to the music and lyrics but not the right to reproduce it commercially, etc). All those different types along with splitting ownership between several artists plus a record company or two is how people end up in court.
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which sums up how it works in a perfect world:
The U.S. Copyright Office considers joint copyright owners to have an equal right to register and enforce the copyright. Unless the joint owners make a written agreement to the contrary, each copyright owner has the right to commercially exploit the copyright, provided that the other copyright owners get an equal share of the proceeds.