A definition of copyright is in order here because ... if you think (or hope) a work is in the public domain you’ll need to know why it isn’t protected by copyright. And a good question to ask right away is “is the work eligible for copyright protection?” There’s no sense grappling with questions about copyright formalities and copyright duration if you don’t need to, right? So here goes ... a definition of copyright. What it is, what it protects, and what it doesn’t protect.
Copyright is a form of legal protection provided to the authors of “original works of authorship,” including literary, dramatic, musical, artistic, and certain other intellectual works. This legal protection is available to both published and unpublished works. In the United States, the copyright statute is Title 17 of the US Code.
According to the US Supreme Court, an original work of authorship is one that hasn’t been copied from another source (that is, it was independently created), and that displays a minimal level of creativity.
A definition of copyright often includes the phrase “bundle of rights.” That’s because anyone who owns the copyright in a work has exclusive rights to:
Note: Copyright ownership is distinct from ownership of the thing in which the copyrighted expression is embodied. If I create a painting, I own the copyright in it — and if I sell the painting I still own the copyright. Transferring ownership of the thing does not transfer the copyright. If I wanted to do that, I’d need to do it by way of a written agreement. See 17 USC § 202.
A work is protected by copyright as soon as it’s fixed in tangible form. “Fixed in tangible form” means you can see or hear or touch the work, whether by looking, listening to, or touching the thing itself ... or perceiving it by means of a machine or device (like a movie projector or a computer).
You don’t have to register with the Copyright Office to get a copyright. You used to, but not anymore. (But you do need a registration if you want to sue someone for copyright infringement).
You don’t have to mark your work as copyrighted, either. (That used to be required, too.) But marking a work as copyrighted gives people notice that someone owns the legal rights, so most copyright owners do put notices on their works.
Probably the safest approach is to assume that all works you encounter, marked or not, are protected by copyright. (I guess what they say about assuming things doesn’t apply here.) Start with that assumption and work from there.
But listen ... increasingly often, copyright notices (complete with stern warnings) appear on works that really are in the public domain — so do your homework and don’t let any “copyfraud” bullies push you around.
Copyrightable works include those that can be categorized as:
But it’s only the specific expression in the work that gets legal protection. The ideas expressed in a work are not copyrightable.
Which leads us to ... what can’t you copyright?