In the first half of the 1990's BSD was sued by Unix Systems Labs, who had bought the rights to AT&T Unix, claiming copyright infringement [0]. It took a couple

In the first half of the 1990's BSD was sued by Unix Systems Labs, who had bought the rights to AT&T Unix, claiming copyright infringement [0]. It took a couple of years for everything to be dismissed and settled. "Ultimately, the legal drama did not undercut programmers’ ability to use or redistribute BSD. However, it did stunt adoption of the operating system by creating doubts about BSD’s legal future. As a result, it arguably forged an opening that allowed Linux to gain ground despite being developed primarily by an undergraduate in his Helsinki apartment, rather than a team of professional computer scientists at a major American university." I've always heard that this lawsuit was significant, ruining the momentum that BSD had at the time, momentum that ended up shifting to linux. [0] https://www.channelfutures.com/open-source/open-source-history-why-didnt-bsd-beat-out-gnu-and-linux https://www.channelfutures.com/open-source/open-source-histo...