It's also quite funny that Quaid (who made copywrite) was sued by a protection vendor... but won!

"We hold that: (1) Quaid did not infringe Vault's exclusive right to reproduce its program in copies under § 106(1); (2) Quaid's advertisement and sale of RAMKEY does not constitute contributory infringement; (3) RAMKEY does not constitute a derivative work of Vault's program under § 106(2); and (4) the provision in Vault's license agreement, which prohibits the decompilation or disassembly of its program, is unenforceable."

in https://cyber.harvard.edu/ilaw/Contract/vault.htm

Edit: there is a Wikipedia page for that https://en.wikipedia.org/wiki/Vault_Corp._v._Quaid_Software_.... (there is a dot at the end of the URL but HN parser does not treat it correctly)