Massive Steam Data Leak Exposes 12TB of Game Assets from 2003-2013
A leak containing builds of every game uploaded to Steam over a decade has surfaced previously unseen developer content and canceled titles.
What happened
Over 12 terabytes of data containing builds of games uploaded to Steam between 2003 and 2013 has been leaked. Researchers have already identified abandoned Half-Life 2: Episode 3 assets, cut content from Portal 2 including deleted dialog and alternative sequences, and builds of early versions of commercial titles including Call of Duty, Resident Evil, Mirror's Edge, Batman: Arkham Asylum, and Dragon Age: Origins. The archive also contains a previously unknown game called F-Stop set in the Portal universe built around a camera mechanic, as well as a version of the Weaponizer tool intended for Half-Life 2: Episode 3.
Context
The scale of the leak—covering a decade of Steam submissions from both Valve and third-party developers—means additional unreleased or canceled content may continue to surface as researchers examine the archive. The discoveries provide a rare window into abandoned development branches and editorial decisions, such as Portal 2's cut content that alters understanding of in-game elements. This type of leaked source material is typically kept private by developers and publishers.