Breakdown of Собственник подписал протокол.
Questions & Answers about Собственник подписал протокол.
Because it is past tense, masculine, singular.
In Russian past tense, the verb agrees with the subject in gender and number:
- подписал = he signed / a masculine subject signed
- подписала = she signed / a feminine subject signed
- подписало = it signed / a neuter subject signed
- подписали = they signed / plural subject signed
Since собственник is a masculine singular noun, the verb is подписал.
It is in the nominative case because it is the subject of the sentence — the person who performed the action.
So in:
- Собственник подписал протокол.
собственник = the owner / proprietor
This is the one who did the signing.