What are these crude markings on the back of lugs from 60's-70's watches

pennsyl936 · Dec 23, 2023

I have seen similar markings on a variety of vintage watches from the 1960's-70's. They are most often rather crude and illegible. I have long guessed they were some sort of personal identification number etched by the owners. Does anyone know what these might represent?

I'll sort through my files and try to find other examples.

This one is from a mid 60's Omega 165.002.

S.H. · Dec 23, 2023

Id numbers scratched by watchmakers after servicing. Usually it is done inside the case back, some did it outside. Easier to check if the watch is still under warranty 🙄.

Evitzee · Dec 23, 2023

Some retailers, Tiffany for one, used to scratch mark all their articles prior to sale if the size allowed it.

DaveK · Dec 23, 2023

Not just watchmakers, my wife does a similar things to our car, reminding her which parking lot pillars to avoid

Plees · Dec 23, 2023

DaveK
Not just watchmakers, my wife does a similar things to our car, reminding her which parking lot pillars to avoid

Off course with all parking assistance on board?😎

lucreative · Nov 18, 2025

Bring up this thread again since my newly received Seamaster 105.004 14k from 1965 with had these numbers on the lugs too. Any additional ideas? It looks stamped and not crudely marked by a watchmaker.

Dan S · Nov 18, 2025

lucreative
Bring up this thread again since my newly received Seamaster 105.004 14k from 1965 with had these numbers on the lugs too. Any additional ideas? It looks stamped and not crudely marked by a watchmaker.

That may match some numbers in the caseback.

Vitezi · Nov 18, 2025

lucreative
Any additional ideas?

Back in the day (1940s, 50s), three or four digits of the caseback serial were sometimes stamped onto the back of the lugs, probably to help coordinate final assembly. I'm not sure if that practice continued into mid-1960s on gold watches.

lucreative · Nov 19, 2025

Dan S
That may match some numbers in the caseback.

No matching numbers on the case back.

lucreative · Nov 19, 2025

Someone from the UG sections posted about similar engravings on the lugs of his solid gold UG as well, not scratches like the OP had on his lugs. Another poster mentioned that this could be inventory number from watches sold by Cartier Boutiques? Supposedly Pateks, IWC and other non-Cartier watches sold at Cartier Boutiques had these stamps? I wonder how to verify this and is it important to the history? I'm somewhat glad the Cartier name isn't on the dial of this Omega Seamaster 321.