149 nib marking Sle O D ?

[cybaea]

What does the Sle O D (S^le O-with-dot-inside D) marking on the nib of my circa 1993 MB 149 mean? Curious. I couldn't find any information though it is clearly the marking mentioned in ITEM #3970 at http://pentooling.com/montblanc.html . Any ideas?

[jar]

It's Ste not "l" IIRC and no one seems to knows.

[mmahany]

It should be "SToD" and be circled. It's a jewelers trademark used to identify someone's work (Montblanc in this case). Older pens won't have the trademarket, but newer ones will. Montblanc started putting it on their precious metals fairly recently. Of note, all my newer pens have the SToD trademark on the nib. Also, my sterling silver montblanc pens have the trademark on the exterior part of the cap near the rings.