You're right. Janssen Fil ceased trading in 1957. The 12 Gauge 3" Magnum sidelock Ejector in my Avatar, was built by Janssen Freres in 1932. Janssen Freres ceased trading in 1948.I know that some higher end guns sidelocks were built by the firm, but all that I have handled were basic boxlocks or hammer guns. The majority were built prior to WWII. I believe production ended not long after the war. It is interesting to see a double rifle. It seems to follow the utilitarian design of the shotguns I have handled.