Lvov dvoryan families should not be confused with Lvov princely family.
There were several dvoryan (Russian nobility) families named Lvov (ru|Львов) in the Russian Empire.[1]
One of them is traced from a Mark Demidovich of Lithuanian descent (14th century) and is enlisted into the pedigree book of Tver Guberniya.[1]
Another one traces from the 16th century and enlisted into the pedigree books of Moscow and Oryol guberniyas.[1]
Still another one descends from a Kondratiy Afanasiyevich Lvov granted an estate in Galich uyezd, Kostroma Guberniya in 1671. The family is enlisted into the pedigree book of Kostroma Guberniya.[1]