Enormous 12TB Steam leak includes abandoned Half-Life 2: Episode 3 assets

A massive 12-terabyte data leak from Valve has surfaced online, containing internal builds and assets from games developed between 2003 and 2013. The leaked archive includes early versions of several Valve titles, such as Portal 2, Left 4 Dead, and Counter-Strike: Global Offensive. According to The Verge, it also contains assets related to the canceled Half-Life 2: Episode 3, as well as content cut from Portal 2.

The leak, which was first flagged by Twitter user Gabe Follower, includes a 2009-era Portal 2 beta build, a fully playable Left 4 Dead beta build dated June 2008, and builds of games from third-party developers, including Call of Duty and Resident Evil installments, Mirror's Edge, Batman: Arkham Asylum, and Dragon Age: Origins, as reported by The Verge. Eurogamer notes that the archive also contains assets from the canceled Portal prequel F-Stop.

The leak is thought to be a result of an accessible endpoint to Valve's legacy infrastructure, rather than a hack or security breach, as reported by Tom's Hardware. The files are still being explored, but they provide a rare insight into Valve's projects during a period when the company was a more active game developer.

Brief written by urgent.news from The Verge, Eurogamer, Tom's Hardware, PC Gamer — 4 reports on this story. Machine-written — may contain errors; check the original before relying on it.