Greenlaw (groin) was activated from injured reserve Saturday, Matt Maiocco of NBC Sports Bay Area reports.
Greenlaw was injured in the first game of the season and has been sidelined since after undergoing core muscle surgery. He returned to practice prior to the team's Week 11 game Jacksonville and is now set to return for a Week 12 matchup against Minnesota. Greenlaw should play a key role among the team's linebacker corps, as he recorded six tackles and returned an interception for a touchdown in his lone contest on the campaign.