// KOTAKU — GAMING
Colossal 13TB Steam Leak Reportedly Includes Beta Builds Of Portal 2, Left 4 Dead 2, And Much More
Thirteen terabytes of Steam depot data, reportedly spanning from 2003 to 2013, has leaked online within the past 24 hours. The leak has been made publicly available via a torrent file, and those investigating the contents have reported that it contains beta builds for thousands of games, including Portal 2, Left 4 Dead 2, Dragon Age: Origins, and Batman: Arkham Asylum.
Exactly who obtained the leaked data in question is currently unconfirmed, but the leak appears to be very real and can easily be found online. Given the size of the leak, it’s taken people some time to sort through it all, but a list of the contents discovered so far is being actively cataloged on GitHub.
It’s important to note that the “Steam2” leak, as it’s been dubbed, contains data spanning from 2003 to 2013. Considering how much video game file sizes have ballooned in the last decade, 13 terabytes of pre-2014 data is a bigger deal than some might initially assume.
(1/2) That Valve leak that just happened a few hours ago might actually be one of the biggest video game leaks of all time. It will be interesting to see how this all goes down.
Basically a shit ton of beta builds uploaded to Steam in-between 2003 – 2013 has leaked.
— AestheticGamer aka Dusk Golem (@AestheticGamer1) August 30, 2026
With this in mind, there’s a lot of unconfirmed info going around out there at the moment. This is essentially my way of warning you that you should take any purported Half-Life 3 “leaks” with an extra carton of salt for the next week or two.
However, there are a couple of interesting things that have already been confirmed, such as the existence of a Portal 2 beta.
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… There's a Weaponizer… pic.twitter.com/Sg7OqJjL2X
A few videos of people playing through it have started cropping up online, which is likely why Elan Ruskin, an ex-Valve developer who worked on the likes of Half-Life 2: Episode Two, Left 4 Dead 2, Portal, and Portal 2, chose to address the existence of the “prerelease” builds of Portal 2 and Left 4 Dead 2 in a post on X earlier today.