IBM also had experience of the 8085 and 8086 from their System/23 and Displaywriter systems which meant there was previous experience with Intel microprocessors

IBM also had experience of the 8085 and 8086 from their System/23 and Displaywriter systems which meant there was previous experience with Intel microprocessors in IBM at that time. I also read somewhere (but do not have a source to hand) that IBM had a significant investment in Intel at that point in time.