Adidas has filed an appeal in a federal court in Washington, D.C., to uphold its rights in its long-standing patent dispute with Nike over their knitted shoe uppers. Adidas is trying to reverse a Feb. 19 ruling by the appeals board of the U.S. Patent and Trademark Office which found that it didn't have enough evidence to invalidate Nike's patent claims over its Flyknit technology. Nike launched the technology at the 2012 London Olympics, at about the same time as Adidas' Primeknit technology was launched. German court rulings initially upheld and then set aside Nike's claims against Adidas. Based on the latest state of affairs, anyone can make a one-piece knitted upper for sale in the European Union, but the battle is not yet over in the U.S.