Court Injuncts Ridge Corp.’s Green Tail Aero-Device Business
Judge Beverly Reid O’Connell of the United States District Court for the Central District of California on August 24 granted Stemco subsidiary ATDynamics’ Motion for a Preliminary Injunction against Ridge Corporation’s Green Tail aerodynamic-device business.

TrailerTail panels fold out to reduce aerodynamic drag. Photo: ATDynamics

Judge Beverly Reid O’Connell of the United States District Court for the Central District of California on August 24 granted Stemco subsidiary ATDynamics’ Motion for a Preliminary Injunction against Ridge Corporation’s Green Tail aerodynamic-device business.
According to an August 26th Stemco statement, the court found that ATDynamics had demonstrated it is “likely to succeed” on the merits of its patent infringement lawsuit against Ridge, based on the court’s review of three representative claims.
Stemco said that the court has ordered Ridge Corp. to immediately cease all manufacture, use, sales, offers for sale or importation of Green Tail devices or any other products that infringe on one or more claims of U.S. Patent Nos. 8,360,510, 8,360,509 or 8,272,680.
“This injunction will stop Ridge’s infringement of ATDynamics’ patents while the patent infringement lawsuit is ongoing,” Stemco stated. “ATDynamics has also asked the Court for monetary damages and to make the injunction against Ridge permanent at the conclusion of the lawsuit."
In reply to an HDT request for comment on the injunction being granted, a statement provided by Ridge Corp. President Gary Grandominico asserted that “Ridge categorically denies the allegations that the GreenTail infringes ATDynamics’ patents, and also denies that ATDynamics’ patents are valid.”
In addition, Ridge said that due to the court granting the injunction, the company “will be unable to sell its GreenTail devices while the parties conduct discovery and litigate the infringement, invalidity and other issues in the case.”
Ridge also stated that “The court has not held that Ridge’s product infringes any of ATDynamics’ (STEMCO) patents and has not held that ATDynamics’ (STEMCO) patents are valid. These issues will be decided in due course in the litigation.
"However," the company added, "the decision does prevent Ridge from offering its GreenTail device to the market for the indefinite duration of the preliminary injunction. Ridge regrets that, as a result of the pending litigation, it will be unable to satisfy its customers’ requests for the GreenTail product.”
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