A decade's worth of Steam files totaling more than 12TB has leaked

The leak contains beta builds and finished games from Valve and third-party developers. A decade’s worth of Steam files totaling more than 12TB has leaked. Gaming A decade’s worth of Steam files totaling more than 12TB has leaked The leak contains beta builds and finished games from Valve and third-party developers.

The leak totals more than 12TB in scale and includes beta builds and completely finished games from Valve’s own franchises, including Half-Life, Left 4 Dead and Portal. A GitHub catalog has compiled most of the titles, which also includes games from major franchises like Call of Duty, Fallout and Civilization, as well as those from indie developers. Someone leaked 12 TB of Valve’s internal builds and game assets from 2003 to 2013.

This includes early versions of Portal 2, Left 4 Dead, CS:GO, F-Stop and potentially EP3. The community is still researching everything, so the next few days might be insane… Pic.twitter.com/Sg7OqJjL2X — ‎Gabe Follower (@gabefollower) August 29, 2026 The sheer size of the leak means people are still combing through the details, but so far internet sleuths have uncovered details of the unreleased F-Stop game from Valve that features gameplay revolving around a camera that can manipulate real world objects.

Of course there are hints of the long-rumored conclusion of the Half-Life franchise in the leak, but it references Half-Life 2: Episode 3, which was supposed to be the final game in the series but was later canceled.