The spat between ZeniMax Media and Oculus VR escalated to a court battle today, with ZeniMax suing the virtual reality firm for misappropriating ZeniMax trade secrets.

ZeniMax is also throwing in breach of contract, unjust enrichment, and unfair competition into the suit, which was filed in Texas district court and names Oculus VR and founder Palmer Luckey.

At issue is intellectual property, "including trade secrets, copyrighted computer code, and technical know-how relating to virtual reality technology that was developed by ZeniMax after years of research and investment," ZeniMax, a Maryland-based video game publisher, said in a statement.

According to ZeniMax, former employee John Carmack took ZeniMax-owned intellectual property with him to Oculus VR, where he now serves as CTO. "Intellectual property forms the foundation of our business," Robert Altman, Chairman & CEO of ZeniMax, said in a statement. "We cannot ignore the unlawful exploitation of intellectual property that we develop and own, nor will we allow misappropriation and infringement to go unaddressed."

"The lawsuit filed by ZeniMax has no merit whatsoever. As we have previously said, ZeniMax did not contribute to any Oculus technology. Oculus will defend these claims vigorously," Oculus VR said in a statement today.

When news of a disagreement between Oculus and ZeniMax first made headlines, Oculus suggested that ZeniMax is simply seeing dollar signs after its $2 billion Facebook acquisition. Later, Oculus said ZeniMax's accusations are "false."

"ZeniMax did not pursue claims against Oculus for 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," an Oculus spokesman said earlier this month.

Carmack, co-founder of id Software and lead programmer for groundbreaking titles like Wolfenstein 3D, Doom, and Quake, also addressed the controversy on Twitter on May 1.

For more, check out PCMag's Hands On With the Oculus Rift DK2.