The team announced the deal Tuesday.
Bishop joined the Niners last December and played two games. He had two tackles on special teams and one on defense.
Bishop has appeared in 75 games with Green Bay, Minnesota and San Francisco since entering the league as a sixth-round pick by the Packers in 2007 out of California.
Bishop has 319 tackles, nine sacks, seven forced fumbles, one interception and 13 passes defensed in his career.
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