The 49ers activated Sanu (knee) from injured reserve Wednesday, Cam Inman of The San Jose Mercury News reports.
Sanu reached the end of his 21-day window for the 49ers to either activate him from IR or rule him out for the rest of the season. It's unclear if he'll be available for Sunday's NFC Championship Game against the Rams, and it's also uncertain what his role would be if he plays, given that Jauan Jennings has provided solid work as the No. 3 receiver. Sanu caught 15 of 24 targets for 177 yards in eight regular-season games, with his most recent appearance coming Week 9.