Reid, the 18th overall pick in the 2013 NFL draft was the last of San Francisco's 12 draftees to sign a deal with the team. Financial details were not disclosed.
The 22-year-old All American out of LSU played in all 13 games last season, finishing his college career with 199 tackles, six interceptions, two forced fumbles, two fumble recoveries, and 4.5 tackles for loss.
With free safety Dashon Goldson headed to Tampa Bay, Reid is expected to compete for a starting job this fall.
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