Seattle announced Thomas had passed his physical and been added to the active roster following practice on Wednesday.
Thomas started training camp on the PUP list after undergoing offseason surgery to repair the labrum in his left shoulder. Thomas was initially hurt in the NFC championship game but played in the Super Bowl with the injury. He underwent surgery shortly after the Super Bowl and was expected to be ready near the start of the season.
Backup Steven Terrell has been working at free safety early in training camp with Thomas out.
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