Biogen: Did Someone Say Biotech Stocks are Falling?

Despite the market's weakness today, Biogen ( BIIB ) is rising after receiving a positive patent ruling involving its multiple sclerosis drug Tecfidera in its battle with Kyle Bass's Hayman Capital Management . That Biogen is trading higher is no small thing. Not only is the S&P 500 trading off 1% at 2,349.53 at 1:24 p.m. today, but the iShares Nasdaq Biotechnology ETF ( IBB ) has tumbled 2.1% to $290.41. Biogen, in contrast, has risen 0.8% to $277.06 to $277.06. Mizuho's Salim Syed explains what happened--and why the legal battle isn't over yet: