Originally set up to support Unix internally, the Unix Support Group eventually became Unix System Laboratories, and developed the System III and System V commercial versions of Unix.

1973:
USG Release 1.0

1974:
USG Release 2.0

Program Generic Issue 1

1975:
MERT First Edition

1976:
Program Generic Issue 2

1977:
Program Generic Issue 3

PWB UNIX

MERT Release 0

1978:
UNIX/TS

1979:
CB-UNIX

32V Unix

UNIX/RT

PWB UNIX 2.0

1980:
System III

1981:
UNIX Release 4

1982:
UNIX Release 5

1983:
System V