illegal copy; pirated copy
Refers to unauthorized duplication of software, media, or digital content. Common in computing and copyright contexts.
Illegal copying of software is prohibited by law.
彼は映画の不法コピーをダウンロードしてしまった。
He ended up downloading an illegal copy of the movie.
Compound of 不法 (illegal) and コピー (copy), a straightforward modern term.