Adidas has sued Under Armour, claiming that Under Armour’s UA Armour39 product, which includes chest straps, watches and mobile apps used for tracking exercise and fitness infringe on adidas’s patents.

The lawsuit alleges Under Armour had direct knowledge of Adidas competing products because it hired a senior director of engineering from Adidas. Under Armour acquired MapMyFitness in 2013 as many athletic footwear and apparel brands were racing to field products that allowed fitness buffs to track heart rate, speed, distance and other metrics during exercise.

The lawsuit alleges that Under Armour has infringed on 10 adidas patents and asks the court to stop sales of the products in question.