Two of the world’s biggest activity tracking companies are now primed for a nasty legal dust-up.

Jawbone filed suit against Fitbit in a California State Court yesterday, alleging that its opponent had stolen confidential company information. Jawbone says that Fitbit systemically poached employees, who downloaded sensitive presentations and product plans prior to departing the company, reports The New York Times.

The suit arrives on the heels of Fitbit’s IPO filing earlier this month, in which the company touted its dominance in wearables -- having sold 21 million devices since its founding in 2007 and comprising 85 percent of the U.S. connected activity tracker market, according to NPD data cited in its prospectus.

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In the suit, Jawbone claims that Fitbit contacted one-third of its employees earlier this year -- several of whom downloaded documents onto thumb drives and then used programs to conceal this activity.

One such hire, Ana Rosario, is accused of participating in a private meeting with senior management after having already accepted a position at Fitbit. Rosario also admitted to downloading Jawbone’s ‘Market Trends & Opportunities’ presentation, according to the complaint.

“As the pioneer and leader in the connected health and fitness market, Fitbit has no need to take information from Jawbone or any other company,” Fitbit said in a statement to the Times. “We are unaware of any confidential or proprietary information of Jawbone in our possession and we intend to vigorously defend against these allegations.”

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