According to IBM’s filing, Papermaster "is privy to a whole host of trade secrets and confidences belonging to IBM", a position that legally required him by contract to "refrain from working for an IBM competitor for one year". Papermaster has been with IBM for over 26 years and is rated as a top expert in IBM’s Power microprocessor architecture
With him leaving to Apple, IBM fears that the latter would use Papermaster’s know-how to develop server and chip products that would rival its own. Also, given the fact that Apple has acquired P.A. Semi earlier this year, IBM also fears that Apple might be thinking to give up on the IBM Power chips with chips made by P.A. Semi.
IBM informed the court that Papermaster had been offered one year’s salary just to make sure he would respect "his contractual obligation to refrain from working for an IBM competitor for one year," but the offer was made in vain.
Accordign to the filing, Papermaster told IBM on October 21 of his intentions to start working for Apple beginning in November and submitted his resignation.