The move was announced Friday.
Stone was injured in practice this week and had already been declared out for the Falcons' game Sunday at Jacksonville. He played in seven games this season with one start. Now he's done for the year.
Outside linebacker Tyler Starr was promoted from the practice squad. He was a seventh-round pick in 2014 and had yet to play in a game for the Falcons.
Atlanta (6-7) is mired in a six-game losing streak after starting 5-0.
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