Where does “-ов” come from?

-ов (Russian) comes from Old East Slavic -овъ, from Proto-Slavic -ovъ — of, belonging to.

Ancestry of “-ов”, step by step

Step	Language	Word	Meaning
1	Old East Slavic	-овъ	—
2	Proto-Slavic	-ovъ	of, belonging to

-ов — Etymology, Origin & Word History | Etymology Explorer