The H&K and GSG Lawsuit

You may remember back in 2009, H&K sued German Sports Guns (GSG) and ATI because GSG manufactured a .22 firearm that looked like the MP-5. (See also here). Recently it was reported that GSG is claiming that H&K committed fraud in obtaining the settlement because it does not actually own the design of the MP-5.

To understand GSG's arguments, you have to understand the history of the H&K roller-lock system. And that takes us back to the end of WWII, when some German arms designers fled to Spain to set up a company known as Centro de Estudios Técnicos de Materiales Especiales (CETME) to perfect their roller-lock design. The result was the CETME Model B in 7.62 NATO.

CETME Model B

Although West Germany initially adopted the FAL (under the German G-1 designation), Belgium refused to license the design to Germany for it to make its own versions. Casting about for a replacement, the Bundeswehr decided on the basic system developed by CETME and purchased the production rights.

G3A3

Early versions of the G-3 were very similar to the CETME, including wood furniture, a rear flip sight that could be changed between two apertures, and even had "CETME" stamped into the receiver. Most the changes to the G-3 were internal (the G-3 and CETME are actually quite distinct in how their trigger and seers work), and modifications to the sighting system. Over time, the stocks evolved from the round-wooden front stock similar to that of the CETME, to a round plastic forestock and synthetic butt-stock, to the angular plastic forestock of later models. (See here). 

H&K adapted the design to other weapons, including the G33 and the MP5.

MP5-A2

Some of the "look" of the weapon, such as the paddle release, the "slot" along the side of the receiver, the use of a triple frame front sight assembly, the cocking handle, and so on, are clearly from the CETME. However, the specific shape of the front sight assembly, the rear drum sight, and the overall look of the newer "Navy" lower receiver are distinctive to the H&K weapons. 

GSG-5

I would not hold high hopes for GSG. It will be interesting to see how this turns out.