Scott Fox's senior career began at East Fife in season 2007-08
Scott Fox cited the incentive of European football after moving to Motherwell on a one-year deal.
The goalkeeper made 31 appearances for Partick Thistle last season, having previously spent five years at Firhill before joining Ross County.
Manager Stephen Robinson described the 32-year-old, who will vie with Trevor Carson for the number one spot, as a "strong addition".
"Scott's attitude has impressed me in his short time with us," he said.
"He's a keeper with Premiership experience."
Fox, who has been training with the Fir Park outfit for the past week, told the Motherwell website., external: "I'm here to fight for the right to play.
"Trevor is a tremendous goalkeeper who plays at international level and it's my job to push him as much as I possibly can.
"It's an improving side which want to be challenging up the top end of the table and obviously this year there's European football. It's a great time to join."
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