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

[pennsyl936]

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.]

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]

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

 

[DaveK]

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

 

[Plees]

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?😎