He had won the Aruvikkara assembly bypoll. He took the oath in the name of God in the assembly.
Sabarinadhan, the son of former Speaker G Karthikeyan, whose death necessitated the bypoll, is an engineering graduate and an MBA degree holder.
In one of the fiercest triangular poll battles fought in the state in recent times, Sabarinadhan won the seat by a margin of 10,128 votes against his nearest rival M Vijayakumar (CPI-M) of LDF Opposition who was polled 46,320 votes. BJP candidate and former union minister, O Rajagopal, got 34,145 votes.