Stupar was released by the Jacksonville Jaguars on Saturday. Stupar was a seventh-round pick by Oakland in 2012 and also has spent time with Philadelphia and San Francisco. He was waived by the 49ers after appearing in five games last season.
The Falcons also signed eight players to their practice squad who were with the team in the preseason. Among those signed to the practice squad were two 2014 draft picks - cornerback Ricardo Allen and defensive tackle Travian Robertson.
Also signed to the practice squad were offensive linemen Harland Gunn and Terren Jones, safety Sean Baker, wide receiver Bernard Reedy, linebacker Jacques Smith and running back Jerome Smith.
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