Seeing double

Carl Icahn has sold almost half of his stake in Biogen Idec Inc. (NASDAQ:BIIB) over the last few months for about twice what he paid for it.

He's cashing in on a steep appreciation of the shares over the last year on new management, a test to help determine Tysabri natalizumab patients at risk for progressive multifocal leukoencephalopathy (PML), and positive Phase III data for multiple sclerosis candidate BG-12...