According to Stemco, a federal court has scheduled a hearing on its request for a preliminary injunction against Ridge Corp. for alleged patent infringement involving the TrailerTail product of Stemco’s subsidiary, ATDynamics.

The hearing in United States District Court for the Central District of California is scheduled for July 13, Stemco said. It is asking the court to order Ridge to stop making and selling its Green Tail aerodynamic device because it infringes on at least five ATDynamics patents.

TrailerTail uses several thermoplastic panels that fold out to form a boat tail to reduce air drag at the trailer’s rear. Stemco, which bought ATDynamics early this year, says Ridge’s Green Tail is too similar to be legal, and thus the suit.

The Green Tail is still listed by the Environmental Protection Agency as a verified technology on its SmartWay website. However, Green Tails is not among the products now included on Ridge’s website, which does list its Green Wing trailer skirts and wall liners. A call to Ridge in Patascala, Ohio, asking for comment was not returned.

District Judge Beverly Reid O’Connell is handling the case, Stemco said in a statement.

“Stemco-ATDynamics has engaged Timothy Carroll and Kourtney Merrill of powerhouse IP law firm Perkins Coie to protect its intellectual property rights,” the statement said.

“Perkins Coie is one of the top ranked law firms in the country for patent law and patent litigation, was named Patent ‘Law Firm of the Year’ for two consecutive years (2013, 2014) by U.S. News – Best Lawyers, and is routinely ranked as one of the most hired firms for patent litigation in the United States.”