1949.
write to marlin with any and all writngs/markings on reciever/barrel and serial numbers
1949
call marlin
If it is marked Light 12, that is an incomplete serial number.
the age of a model 12 shotgun can be determined by the serial number.
Impossible to answer without the serial number.
No serial number provided.
1950
1937
behind the rear sight bracked on the left side just above the stock
How much is a Marlin 12 gauge pump shotgun with a Pat D Nov 6 1894 May 12 1896 June 2 1896 on barrel with serial #80996 is worth.