Oculus Rift is set to launch in late 2014 or early 2015. Courtesy/Oculus VR

Facebook Inc. (NASDAQ:FB) is blasting legal claims of intellectual property theft against Oculus, which it agreed to acquire in March.

Oculus, maker of the popular virtual reality (VR) headset known as the Rift, is being sued by ZeniMax Media over its claims that John Carmack used stolen intellectual property to develop the Rift. Oculus used software made by Carmack while he was a ZeniMax employee, the company claims, which is why the two-year-old company has been able to fast-track production of the Rift.

Oculus sells the Rift to game developers and anyone willing to pony up $350 for a gadget still in the testing phase and not yet considered a "consumer product."

Facebook, which in March announced its plan to buy Irvine, California-based Oculus for $2 billion, on Monday said it will “prove” that all of the suit’s claims are false and released seven talking points regarding Carmack. He gained fame for producing video games “Doom” and “Wolfenstein 3D" for id Software before it was acquired by ZeniMax Media in 2009.

Last week Carmack took to Twitter, claiming that no work he had done was patented, and while ZeniMax may own his code, “they don’t own VR [headset technology].” He said “Oculus uses zero lines of code that I wrote under contract to ZeniMax.”

“We are disappointed but not surprised by ZeniMax’s actions,” Oculus said in a statement emailed to the press. “We will prove that all of its claims are false.” Oculus makes the following seven points:

  1. 1. There is not a line of ZeniMax code or any of its technology in any Oculus products.
  2. 2. John Carmack did not take any intellectual property from ZeniMax.
  3. 3. ZeniMax has misstated the purposes and language of the ZeniMax non-disclosure agreement that Palmer Luckey signed.
  4. 4. A key reason that John permanently left ZeniMax in August of 2013 was that ZeniMax prevented John from working on VR, and stopped investing in VR games across the company.
  5. 5. ZeniMax canceled VR support for Doom 3 BFG when Oculus refused ZeniMax’s demands for a non-dilutable equity stake in Oculus.
  6. 6. ZeniMax did not pursue claims against Oculus for intellectual property (IP) or technology, ZeniMax has never contributed any IP or technology to Oculus, and only after the Facebook deal was announced has ZeniMax now made these claims through its lawyers.
  7. 7. Despite the fact that the full source code for the Oculus SDK is available online, ZeniMax has never identified any "stolen" code or technology.
  8. oculus rift john carmack cto
    John Carmack, CTO of Oculus and producer of the "Doom" video game series for id Software, claims that none of the work he did for the developer, which is owned by ZeniMax Media, was used in the Oculus Rift. Oculus

Rockville, Maryland-based ZeniMax Media began seeking compensation for its intellectual property from Oculus in August 2012. Six months later, Oculus offered ZeniMax a small stake in the fledgling VR company, but the two could not reach a deal.

Carmack’s move to Oculus was followed by five more ZeniMax employees earlier this year. ZeniMax asked Cormack in February to disclose any virtual-reality inventions he developer while in their employ, the Wall Street Journal reports.

Following Facebook's deal to purchase Oculus, ZeniMax wrote a letter stating that the Rift was born via ZeniMax technology. "It was only through the concerted efforts of Mr. Carmack, using technology developed over many years at, and owned by, ZeniMax, that Mr. [Palmer Luckey, Oculus founder] was able to transform his garage-based pipe dream into a working reality," the letter said. ZeniMax did not respond to a request for comment.

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