Reebok has sued Nike over patent infringement of "collapsible shoe" technology on Tuesday. The "collapsible shoe" technology allows sneakers to be folded so they can more easily be packed for travel or shipping. Reebok International Ltd., which was acquired in January 2006 by Germany-based Adidas AG, alleged Tuesday that 11 Nike shoe models infringe on a U.S. patent Reebok obtained in January for flexible sole technology.

The models are marketed under the product names "Free," "Free Zen & Now," "Free Trainer," and "Free Trail," Reebok said.

Nike Inc., the world's largest sports apparel company, issued a statement saying the company was "evaluating the claims related to this very recently issued U.S. patent and any potential limited application to the successful Nike Free product."