Jacobs signed with the Niners in the offseason but was unable to begin the year with the team due to a knee injury sustained in the preseason. He was ready to go by Week 4, but the Niners have only dressed him for three games this season. Jacobs has been extremely vocal about his lack of playing time and the way he has been treated by head coach Jim Harbaugh and the organization.
The Niners have apparently had enough of Jacobs and chose to suspend him rather than release him. This way he can't sign with another contender such as the Giants or Packers, where he could end up hurting them in the postseason.