The Falcons re-signed Kwiatkoski on Thursday, Tori McElhaney of the team's official site reports.
Kwiatkoski was released ahead of Tuesday's 53-man roster deadline, but he's since returned to team after the Falcons opened up numerous roster spots by placing a plethora of players on IR. The veteran linebacker is expected to share backup duties with rookie Troy Andersen behind the starting duo of Rashaan Evans and Mykal Walker.