http://seekingalpha.com/article/1046581-the-reason-behind-apple-s-beating http://seekingalpha.com/article/1046581-the-reason-behind-ap... "“At this point, the

http://seekingalpha.com/article/1046581-the-reason-behind-apple-s-beating http://seekingalpha.com/article/1046581-the-reason-behind-ap... "“At this point, the most plausible explanation is not very reassuring. It seems that COR Clearing is increasing Apple’s margin requirements to 60% from 30% due to excessive concentration,” Santos writes. “This is supposedly leading to mechanical selling to re-establish maintenance margins of leveraged traders.”