Like many, I always wondered how Ruger got away with creating their own version of the Kel-Tec P3AT with no apparent pushback from Kel-Tec for patent infringement. I had always assumed they simply hammered out an agreement whereby Ruger would license or pay royalties for the use of the firing system design created by George Kellgren. In this interview, George Kellgren simply states that they couldn't afford the patent at the time!
https://blog.keltecweapons.com/30-ye...keltec-history
George Kellgren: "Then came the P32. That is actually quite remarkable because it's a pocket handgun that has a lock breach. Before that, all pocket guns were only blow-backs. Traditional blow-back guns tend to be very heavy and expensive to manufacture so, I would say the P32 is the gun that has had the biggest impact on the industry. Everybody copied it.”
George Kellgren: “Unfortunately, those days we couldn't afford the patent. After the P32 came the Sub-9 and then the SUB-2000. And after that you get the PMR-30, KSG.”