According to BingeGamer, Activision has not paid royalties to Infinity Ward over the success of Modern Warfare 2.

The article cites sources “associated with Activision” who says this could be one of the reasons for the confrontation between publisher and developer earlier today.

BingeGamer also mentions that Infinity Ward have been looking for a new deal with another publisher.

IW is contracted to Activision as a developer until October, and it’s rumoured that Activision’s move is a power play to try and bully Infinity ward into staying with Activision. Both developer and publisher owns equal parts of the Call of Duty Franchise, so Activision might be moving to acquire IW’s half of the CoD name.