Ridder was signed by the Raiders off of Arizona's practice squad Monday, Tom Pelissero of NFL Network reports.
Ridder has yet to appear in a game this season while spending the entirety of the year to this point with the Cardinals' practice unit. The quarterback now will be on the Raiders' active roster for at least three games, presumably serving as the top backup option behind Gardner Minshew while Aidan O'Connell (thumb) is unavailable. Ridder appeared in 15 games with the Falcons in 2023, producing 2,836 passing yards, 12 touchdowns and 12 interceptions while also adding 193 yards and five scores on the ground.