Nike and Reebok have co-existed somewhat peacefully on the legal front over the last 25 years despite a turbulent and very competitive fight in the 80’s over the top spot in the U.S. athletic footwear market.

The competition seemed to cool somewhat over the last ten years as Nike pulled away from the field, leaving Reebok to fight for the number two spot with adidas.

The recent peaceful co-existence was upset a bit last week as Reebok filed suit in U.S. district court in Texas against Nike, claiming Nike’s Free line of shoes infringe on a Reebok patent for “collapsible shoe” technology covered under the so-called ‘190 patent.

While Reebok has not hesitated to defend its designs and patents in the past, this move against Nike may signal that adidas Group, Reebok’s new parent, will utilize all tools in its arsenal in their attempts to trip up their larger rival.
Reebok said it filed the suit in the Eastern District of Texas because Nike regularly conducts business in the district and state and has “committed acts of patent infringement and/or has induced or contributed to acts of patent infringement by others” in the district.

Nike filed a patent suit against adidas in the same district in 2006, claiming that adidas’ adidas_1 shoe and the a3 line of shoes, among others infringed upon Nike’s so-called ‘796 patent. A recent report from PricewaterhouseCoopers LLP said the district ranked second among the most favorable for patent infringement lawsuits from 1995 to 2006.

The complaint filed on April 4 identifies several Nike men’s and women’s “Free” shoes that Reebok claims infringe upon its patented flexible sole technology, which also allows shoes to be collapsed for travel or for packaging. The alleged infringing products include Nike shoes marketed under the Free 7.0, Free 5.0, Free 4.0, Free Flex, Free Zen & Now, Free Trainer, Free Flex 4.0 TR and Free Trail 5.0 lines, among others. Reebok indicated in a release that its patent, which was issued in January of this year, “protects technological design features of a system that includes flexible materials in the product’s sole.”

Reebok claims that Nike “willfully and intentionally” developed shoes that use Reebok’s technology, despite the patent protection.
In a statement to the media, Nike said it was “evaluating the claims related to this very recently issued U.S. patent and any potential limited application to the successful Nike Free product.”

Nike first launched the Free 5.0 line in 2005, promoting the product and its flexible components as a way for runners to get similar benefits to those seen from running barefoot.
Reebok first applied for the patent with the U.S. Patent and Trademark Office for the collapsible shoe technology in 2002, describing the innovation as a shoe made from a flexible sole and upper material that can “be rolled, folded or collapsed on itself” in order to be easily stored or carried in luggage.

The patent states that Reebok sees an opportunity to sell product using the collapsible technology in vending machines at airports, train stations or hotels.