Magpul are suing four magazine manufacturers, Big Rock Sports/Swampfox, Cole Industries, Plinker Tactical and Promag, for infringing on their 2009 patent No. 8,069,601 which describes the Magpul PMAG 30 magazine.

The press release …

Magpul Industries Corp announced today that it has filed patent infringement lawsuits against four companies for offering for sale, selling, and distributing magazines for AR15/M16 compatible weapons in violation of Magpul’s patents.  The company’s lawsuits allege infringement of Utility Pat. No. 8,069,601 for a novel ammunition magazine, in addition to numerous Magpul design patents.

The lawsuits, filed in United States District Court, Colorado, provide another example of Magpul’s dedication to protecting its valuable brand while sending a warning to others attempting to infringe on our innovations. “These patents exemplify the industrial design-focused spirit at Magpul, which drives us to create novel solutions that enhance user experience with our products,” said Duane Liptak, Director of Product Management and Marketing for Magpul Industries. “People who use Magpul products have high expectations and a great deal of trust regarding the value, quality, and amount of thought put into every design we release.  As such, we cannot allow others to misappropriate the patented technology that helps us generate that consumer confidence and trust.”

The lawsuits are the largest and most significant to date brought by Magpul, and are part of the company’s ongoing proactive efforts to combat the unlawful production, distribution, and sale of products that infringe on its valuable intellectual property rights.

The abstract of patent No. 8,069,601 is as follows …

The present invention is an ammunition magazine, preferably made of a glass fiber reinforced polymer, utilizing a structurally enhancing ridge, angular guide rails and a follower made to interface with said guide rails to reduce wobble. The preferred embodiment also features a protective cover that distributes forces from the spring to more structurally sound areas of the magazine, thus reducing feed end splay, and an ammunition indication system comprised of at least one window and a noticeable marker on the follower spring. The follower and magazine casing are also designed to interface to prevent the follower from popping out of the feed end and the floor plate of the magazine utilizes a locking plate and sliding relationship between the floor plate, locking plate and magazine to secure the floor plate onto the magazine casing. The cover features built in tools for, among other things, unloading and disassembling the magazine.