Turtle Rock Studios
|Industry||Computer and video games
Michael BoothPhil Robb (co-founder)
|Headquarters||Lake Forest, California, U.S.|
|Products||Video game industry|
Turtle Rock Studios is an American video game developer founded in March 2002 by Michael Booth and Phil Robb, and was acquired by Valve Corporation in 2008. One year later in 2009 Turtle Rock went independent. Turtle Rock Studios is involved in the creation of original titles as well as the provision of consulting services to the digital entertainment industry.
On November 20, 2006, Turtle Rock Studios announced Left 4 Dead, a co-operative multiplayer action game. The game was built atop the most advanced version of the Source Engine available at the time and introduced version 2 of Turtle Rock's AI technology, which had since been updated from the AI used for the bots in Condition Zero. The game released on Microsoft Windows and the Xbox 360 in November 2008.[dead link]
Later in 2008, Valve shut down Turtle Rock Studios and let all the personnel relocate to Seattle to join them if they wanted to. In 2009 Turtle Rock Studios was reopened, with Valve's blessings, by Chris Ashton and Phil Robb.
On 5 February 2010, Turtle Rock Studios put up a new website declaring they have reformed and are once again working on video games.
On 2 June 2010, Turtle Rock Studios announced the formation of a new division in Turtle Rock called Turtle Rock Garage, a small division based solely on casual games.
On 22 September 2010, Digital Development Management announced they are representing Turtle Rock Studios to find publishers for their games.
On 9 February 2011, Turtle Rock Studios announced they have begun aggressive hiring for their next major title.
On 23 January 2013, Take-Two acquired the rights to the current game, listed as Evolve, in the THQ Bankruptcy Auction
List of games 
- Counter-Strike: Condition Zero, including the Official Counter-Strike Bot
- Various maps for Counter-Strike: Source
- A map named "Halls3" which was eventually included in Half-Life 2: Deathmatch
- Left 4 Dead
- Left 4 Dead 2 (Developed by Valve Software)
- The Passing DLC
- Cold Stream DLC
- Left 4 Dead / Left 4 Dead 2: The Sacrifice
- Leap Sheep (Android)
- "Turtle Rock and Valve Announce Left 4 Dead". Shacknews.
- "Valve Acquires Turtle Rock Studios". Valve Corporation. 2008-01-10. Retrieved 2008-01-10.
- "Features - The Gamasutra 20: 2008's Breakthrough Developers". Gamasutra. Retrieved 2012-02-25.
- "E3: Valve's Lombardi On What Happened To Turtle Rock". Gamasutra. 2009-06-03. Retrieved 2009-06-03.
- "Turtle Rock Garage". Turtle Rock Studios. 2010-06-02.
- "Developer Agency DDM Launches Publisher, Investor Division". Gamasutra. 2010-09-22. Retrieved 2010-09-22.
- Cullen, Johnny. "THQ to publish Turtle Rock’s newest title in 2013". VG247.
- Yin-Poole, Wesley. "Left 4 Dead creator's new FPS is "wild"". Eurogamer.
- http://twitter.com/TurtleRockGang/status/127074749884006403Yes, its [sic] all true. We are using CryEngine 3 for our next title...
- http://twitter.com/TurtleRockGang/status/22016522056 We've been working with Valve on new DLC for Left4Dead 1 and 2.