Where the major issues in Marlins started appearing was 2010,
although it could be argued that anything after 2005 was spotty,
as that is when they offered Marlin up for sale, and the
workers kinda "revolted in place" & started not giving a diddly doo dah.
2010-2015 dates I treat with High Suspicion...
much like any used rifle at a pawn shop or gun show.
Altho, it's good to treat 'em all like that,
because you never know when someone is passing along a problem.
Although, given that ALL manufacturers are using the consumer
as the final Beta Test since around 2001, I've adopted the
"Trust, but Verify" method...which basically means inspect all guns
like a Drill Sgt, CAREFULLY and Thoroughly.
Because sometimes, you find out that the workers had a bad day...
and frakkin D/T'd the bolt instead of pulling it first...