Polerouter Bumper case back marking question

Posts
1,203
Likes
3,054
I don't think I've seen a similar marking before, which suggests to me that it did not originate in the factory.

Watchmaker's marking? Retailer's numbering system? Collector's inventory number? An import mark?

None of which seem particularly likely; I'm just throwing out some ideas.
 
Posts
2,671
Likes
24,908
I don't think I've seen a similar marking before, which suggests to me that it did not originate in the factory.

Watchmaker's marking? Retailer's numbering system? Collector's inventory number? An import mark?

None of which seem particularly likely; I'm just throwing out some ideas.
I agree it is so random but it would be nice to be able to dig something out of these quirks.