Thompkins (hamstring) was waived/injured by the Panthers on Sunday, Darin Gantt of the team's official site reports.
The wide receiver can be claimed by another team until Monday morning. If he goes unclaimed, he will revert to injured reserve and would need to reach an injury settlement with Carolina to play this season. Thompkins signed with the Panthers in late July after getting waived with an injury settlement by the Buccaneers in June.