UNIX System Laboratories, Inc. v. Berkeley Software Design, Inc.

**UNIX System Laboratories, Inc. v. Berkeley Software Design, Inc.** is a notable legal case concerning software licensing and intellectual property rights related to the UNIX operating system. The case arose in the early 1990s when UNIX System Laboratories (USL), a subsidiary of AT&T, sought to enforce its rights over the UNIX operating system against Berkeley Software Design, Inc. (BSDI), which had developed its own version of UNIX based on the Berkeley Software Distribution (BSD).