Briggs played his whole career with the Chicago Bears, playing in 173 games and earning seven Pro Bowl appearances while making a case for the Hall of Fame.
However, it has already been made clear that he would be not returning to Chicago for the 2015 season. The team is ready to move on from Briggs, who struggled with injuries the past two seasons, as they try to rebuild their defense under new head coach John Fox.
The 49ers have expressed interest in a number of linebackers since the surprise retirements of Patrick Willis and Chris Borland. Aside from Briggs, the team has also been linked to Erin Henderson and Mason Foster.
Briggs has also drawn interest from the Cowboys and Buccaneers, where he is familiar with head coach Lovie Smith.