SIG SAUER Files P365 Magazine Patent Infringement Case Against Springfield Ammoland Inc. Posted on The new Streamlight TLR-6 Sub mounted on a SIG P365XL. IMG Jim Grant U.S.A. –-(AmmoLand.com)- SIG SAUER, Inc., filed a lawsuit in the United States District Court for the Central District of Illinois, Rock Island Division, alleging that Springfield, Inc. (Springfield Armory) infringes two SIG patents relating to SIG’s P365 magazine. The P365 has seen tremendous commercial success, due to the innovative design of the high-capacity magazine. In its complaint, SIG alleges that Springfield Armory’s making and selling of certain “Hellcat” branded magazines infringes upon two SIG patents. SIG SAUER is seeking injunctive relief, as well as monetary damages for Springfield Armory’s past and ongoing infringement.