Unix copyright code infringement lawsuit is back from the dead — IBM still under fire from Xinuos over 2003-era bytes

No need to pinch yourself — it is, in fact, 2026, and there was a court hearing last June 22 about IBM allegedly using copyrighted source code in Unix-like products, yet again for the umpteenth time since 2003, a saga that’s part of the Unix wars.

For historical context, Xinuos (formerly SCO) and IBM have been embroiled in legal battles for decades, as the companies cooperated between 1998 and 2001 on developing an Itanium variant of Unix. Since then, SCO has repeatedly and dramatically taken IBM to court, claiming the defendant misused SCO-owned source code from the collaborative effort in its AIX and z/OS products, as well as Linux. Many battles have been fought over who owns the “Unix” name, what code IBM put in Linux, and even FreeBSD.

The latest hearing pertains to a 2021 lawsuit by Xinuos, the company that acquired the remnants of Santa Cruz Operations, more commonly known as SCO. Xinuos’ CEO reportedly once stated the group didn’t purchase SCO just to acquire the right to sue IBM, but the company eventually changed its mind in 2021 and dragged IBM back to court on claims that its conduct and copyright infringement resulted in great damage to Xinuos’ market position.

Xinuos picking a fight with a team of lawyers colloquially known as the Nazgûl is questionable on its own — yet, in the aforementioned 2021 lawsuit, Xinuos added bold claims, such as stating that IBM’s purchase of Red Hat should be reversed under antitrust law, and that the company’s strategy in said acquisition was to destroy FreeBSD — the variant underpinning Xinuos’ wares.

How, exactly, an MIT-licensed operating system would be “destroyed” is an interesting matter. Xinuos stated at the time that “IBM and Red Hat have abused their control over the Unix/Linux operating system market for far too long.” One wonders if Linux users with hundreds of distributions at their disposal would agree that IBM has been pulling their strings all along.

The lawsuit dragged on until 2025, when Xinuos voluntarily chose to drop the antitrust claim (presumably after finding little purchase from the court). It also found itself disabused of the merits behind the copyright complaint, as the New York judge in question framed the claim as time-barred: too long had passed for Xinuos to file a complaint, and original ownership of the code is murky at best. Darl McBride, the SCO executive who launched the original lawsuit, passed away from ALS in 2024.

Xinuos did, however, press on with the copyright issue and requested a hearing for an appeal. And on June 22, 2026, the firm argued in front of a three-judge Second Circuit panel that the previous judge miscast a copyright infringement claim as an ownership claim.