I realize that the Ellis family name may not leap out to you, but you should at least recognize some of Paul H. Ellis’ work from the US Army’s Human Engineering Laboratory (HEL). Remember the elevated sight rib on the Colt ACR prototype? That was one of Paul’s pet projects. Jameson S. Ellis is best known for designing the SYNC-series of multi-tools sold by SOG Knives. (However, he is not the same Jameson Ellis running against Rep. Dan Crenshaw in Texas.)
So far, there is at least one granted patent and two active patent applications for their short-recoil pistol design. Instead of a Browning-pattern tilting barrel, it uses a barrel-mounted, pivoting flapper to lock against the front edge of the ejection port. As the barrel travels to the rear in recoil, surfaces on the flapper are engaged by camming surfaces in the frame’s chassis, pulling the flapper down out of the path of the slide. It gives the side profile of the slide a slightly crushed appearance, but you can see that the slide and barrel are extremely low to the frame.
https://patents.google.com/patent/US10203173B2
https://patents.google.com/patent/US20210262746A1
https://patents.google.com/patent/US20210278158A1
