Do mixtapes have copyrights

Answer 1

Each track has two types of protection: the mechanical right (which protects the underlying work) and the master right (which protects the performance). A repackaging of a set of tracks--say, the "Now That's What I Call Music" compilation CDs--pays for licenses on the mechanical and master rights; a few aspects of the compilation (liner notes, cover art, etc.) can be separately registered.

If you have created a mix tape without licensing the mechanical right and the master right for each track, you have infringed the rights of the copyright holders.