Hmm very nice and in my (very limited) experience very unusual.
I looked at the listing..
Good old Sigsal - Where does he get them all from!!
It looks like the shield is full metal inlay though -
Very nice!!
The reverse says 'Ernst Böhlen' - So it looks like it is a promotional knife.
I found some references to this company on Google - It looks like a logistics company based in Switzerland
I did not do a lot of research - However one interesting fact was that this company was formed in 1991
But of course this knife is pre 1945.
Hmmm - Maybe the company renamed/reinvented in 1991 or it's not related at all.
Time for someone with more time to follow this up!