I would agree that markets are not efficient. Look at the massive swings in stocks levered to mining (Joy Global (JOYG), etc.)- these names move 50% routinely in the recent 6-12 months- its not like the outlook for global metals or manufacturing changes that much in that short of a time.
Take biotech- DNDN moves in particular.
Look at RPRX, particularly last November when many of us scooped up the shares dumped by HBK, XMark and the like. These guys made bad decisions and gave up big money to be made. In fact XMark has had such problems that word is that they have been redeemed out of existence. People make mistakes or trade based on wrong assumptions, or have to trade to meet portfolio needs. All of these provide opportunity.
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