I actually think this a good reason against an increased buyback. Within one day traders have destroyed 8% of the value placed on the company by traders. Imagine if they did that after a huge buyback. It would all be for nothing. Back when the company was at $400 it was undervalued but the $500 mark is pretty high and growth has slowed because of the market. Icahn should buy more though, as much as he can then Apple should release the most hideous iPhone 6 and let traders tank the whole stock. His net gain right now must be sitting at below 4%. His extra $0.5b purchase is a sign of desperation. He's just another sweaty gambler at the table hoping everything will go his way so he keeps upping the stake betting his shirt. Break him Apple, give him a $2b loss he won't forget in a hurry and then do something great later on before he can buy back in.