Normally, it goes like "buy on the rumor, sell on the news", so people bought at $2 "the rumor" and have been selling since the top of $12.50 "the news".
In MRKR's case it's been, "buy on the rumor, then after the news wait a bit to see if all the hype plays out quickly into raising the share price, if not then sell while you still have profits."
I still think it has a good shot at long term success, so if it keeps heading down I'll just buy more in the low 6's and low 5's.
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