According to PFT, Griff Whalen has been activated from the practice squad. The article reads as follows:
"The Colts had taken a look at some older receivers, but went with the younger option on hand.
Whalen has been with them for six games this year, and knows the system offensive coordinator Pep Hamilton and quarterback Andrew Luck are running from their days together at Stanford. He has nine catches for 102 yards this season."