The news immediately stoked speculation that Papermaster's departure might be connected to the negative media attention devoted to the iPhone 4 antenna, but Apple did not indicate whether Papermaster left on his own accord or was asked to leave.
Apple recruited Papermaster away from IBM less than two years ago. The hiring resulted in a legal battle between the two companies over IBM's worries that the executive might take too many of its secrets to Apple.
Apple and IBM reached a settlement in January of 2009 that enabled IBM to keep tabs on Papermater's duties at Apple.
Internal documents that turned up in the legal dispute with IBM revealed that Papermaster was not Apple's ideal choice to lead its iPod and iPhone operations.