While I understand the gist your comment, you probably didn't read the link. This is exactly how the market works: traders don't have time to follow closely all the markets of all companies they are trading, so they will eat whatever canned news they get -- provided it came from a reputable source.

So when JP Morgan issues a memo saying "Formlabs ... could be a threat to incumbent 3D printer solutions at the low-end of the market in the near-term... First take: potential negative for DDD" - and in the exact same week that Wired published a cover page with Bre Pettis and his good-looking MakerBot Replicator 2... well, maybe it's time to lock in the 110% gains you had this year with DDD and move on...