Most Zenit cameras used a M42 or M39 mount (screwmount) which was a universal mount and thus free to license.
A few used the Pentax K-mount (also free, iirc) or Nikon F.
The lens I have (the Helios-44) was made in the first three variants, I believe. It's a great lens—as it should be, since the basic design was "liberated" from Carl Zeiss (a top German lens-maker) at the end of WWII.