Copyright assignment
Definition
The signed paper that moves a logo, a website or code to the buyer.
Why It Matters
A trademark assignment does not carry it and a bill of sale does not either. Copyright moves only by a signed writing from whoever owns it, which on a small business is usually the freelancer who built the site, drew the logo, or wrote the code the operation runs on. Two things make a real one: it names the works, by file, repository or address, and it is signed by the person who made them even where an agency did the billing. A blanket line assigning all intellectual property binds the seller, who frequently never owned the copyright to give. Ask for it while the seller still needs your money, because a contractor with no further business from either side has no reason to sign afterward.
In numbers: On a $4M deal the website, the logo and the booking code came from one contractor paid $18,000, and a single signed assignment is what moves all three.