Scott Boyd has joined Partick Thistle on a three-year contract after a compensation fee was agreed with Livingston at the end of his loan.
Scott Boyd was on loan with Partick Thistle
The 19-year-old defender has made 12 appearances for Thistle as they claimed promotion to Division One.
Boyd told Thistle's website: "The loan move for me has worked out really well and I am absolutely delighted.
"I suppose it was a hard decision to make, but the fact that both sides are now in the same league made it easier."
Meanwhile, 17-year-old striker John McGoldrick has extended his stay with Thistle by signing a new two-year contract.
McGoldrick made five appearances from the bench during the past season.