In a lawsuit Adidas contends that UnderArmour and MapMyFitness, which UnderArmour purchased in November, has violated patents for technology used in mobile devices, such as the miCoach sports watches that allow the wearer to track progress on fitness regimens and find heart rates and other data by use of global positioning technology.
UnderArmour39 products use similar technology, as well, the Baltimore Sun reported Wednesday.
"MapMyFitness has been recognized as a pioneer in this category. We are aware of the lawsuit and are in the process of reviewing the complaint," Under Armour spokeswoman Diane Pelkey said in a statement.
The lawsuit, filed in a Delaware court, says a former Adidas engineering manager now works for UnderArmour, which makes it certain that the company knew about Adidas's patents, one of which was filed in 2004 and granted in 2007, the Sun reported.