_Reposted fromCollege of Engineering._ A storage room at the University of Utah’s Merrill Engineering Building has yielded a priceless piece of computing history from more than half a century ago: a nine-track magnetic tape that could hold the only known copy of an important early computer operating system. Robert Ricci, research professor in the Kahlert School of Computing, first shared the discovery on Mastodon. The tape’s label suggests it contains a copy of UNIX Version 4, a pivotal 1973 release from Bell Labs. Aleksander Maricq, a U Engineering research associate, displays the tape in the Merrill Engineering Building, where he discovered it on July 28, 2025. Photo Credit: Dan Hixson UNIX v4 marked a turning point in computer science. It was the first versions of UNIX to be largely rewritten in the C programming language, paving the way for its portability and massive influence on later operating systems—including BSD, Linux and macOS. Until now, historians and enthusiasts had access only to fragmentary pieces of this early UNIX version. “The UNIX operating system, originally developed at Bell Labs, is the precursor to the operating systems that power our computers, smartphones, and servers today,” Ricci said. “Many of the early versions were only sent to a small number of universities and research institutions, so not many surviving copies exist.” “This version was long thought to be lost forever,” he added. Aleksander Maricq, a research associate in Ricci’s Flux Research Group, discovered the tape while cleaning out a storage room on July 28. The researchers plan to personally transport the reel to the Computer History Museum in the Silicon Valley town of Mountain View, Calif., for careful imaging and preservation. Reading the tape will be challenging: nine-track reels require specialized, aging hardware, and magnetic media degrade over time. There’s also no guarantee that the program is even on the tape; such reels were commonly reused and overwritten. If the data is there and proves recoverable, however, it could open a window into a transformative moment in software history. ### MEDIA & PR CONTACTS * Evan Lerner Director of communications, John and Marcia Price College of Engineering 801-581-5911 evan.lerner@utah.edu