A signing is not imminent, but talks between the two sides could heat up soon, Biderman adds.
The prospect of Sherman re-signing with the 49ers seemed unlikely entering free agency, but a slower market than expected could reunite the two sides.
After the 2021 NFL Draft, head coach Kyle Shanahan also left the possibility of a reunion open, stating San Francisco won't ever rule out bringing back the corner.
Sherman spent his last three seasons with the 49ers as the team's top cornerback, starting 29 games over his first two years with the club and earning one Pro Bowl nod in the process. However, a calf injury hampered Sherman in 2020, causing him to appear in a career-low five games.
The 33-year-old has been one of the NFL's most decorated corners since entering the league in 2011, tallying 36 interceptions and five Pro Bowl selections. Sherman has previously said he wants to sign with a competitive team and play for two more years.