Magic Leap Inc accused one of its former engineers of stealing its technology to create his own augmented reality device for China.

In a lawsuit filed Monday in the U.S. District Court, Northern District of California (San Francisco), the U.S. startup alleges that Chi Xu, who left in 2016, exploited its confidential information to “quickly develop a prototype of lightweight, ergonomically designed, mixed reality glasses for use with smart phones and other devices that are strikingly similar” to the Florida-based startup’s designs.

Xu, who founded Beijing-based Hangzhou Tairuo Technology Co., also known as Nreal, unveiled his own augmented reality glasses at a major Las Vegas trade show in January, touting them as lighter than the Magic Leap One.

Magic Leap released its headset last August after seven years of work and more than $2 billion of investment.

Xu is accused in the suit of breach of contract, fraud and unfair competition.