He later took a job at Microsoft because he wasn't earning a salary or benefits at Ancora, he said in a statement. When he took the job, he told Microsoft in writing about Ancora and the patent, he said.

Microsoft also alleges that Mullor ran programs on his laptop in an effort to wipe any evidence that would show he had downloaded the files. The software giant was able to detect which programs he ran and was able to recover some of the documents that he downloaded, according to the suit.

Also, Microsoft says it has e-mail evidence that in 2004, before Mullor applied for a job at the software company, he was already planning to file the patent infringement suit.

Microsoft contends that Mullor committed breach of contract for failing to disclose his continued involvement in Ancora, stole confidential documents and failed to disclose his intentions regarding the patent infringement suit. The company also believes that it is entitled to a royalty free license for Ancora's patent in part because Mullor didn't tell Microsoft that he knew of the patent even while he knew that Microsoft was still developing its own similar technology.

The company also accused him of fraud, misappropriation of trade secrets and unjust enrichment.