The changes were backed by 72 lawmakers, one was against and one abstained.
According to the amendments drafted by LSDDP members Andrius Palionis and Juozas Bernatonis, a political party registered after a general election, which is parliamentary, will receive state funding from the government.
The Seimas had already tried to adopt this bill initiated by the ruling parties but failed to get a majority after the opposition blocked the bid and fewer than 71 lawmakers voted.
The amendments state that a political party, established after the last general election but having its political group in the parliament, will receive a state subsidy calculated by multiplying the smallest amount allocated to a parliamentary party from the state budget at that moment with the ratio of the number of members of the new parliamentary party and the number of members of the parliamentary party group receiving the smallest subsidy.
LSDDP was founded earlier this year by a group of former members of the Social Democratic Party of Lithuania, who split from the party last year, and currently does not receive any state subsidy.