ARIA (and many biotechs in general), many days *(unless ARIA has specific news driven event) trade directly with the ETF biotech index's (more or less) - - ESPECIALLY on low volume days (like today). My entire screen is red. IBB and .BTK-P are straight down, and its dragging sector with it. IMO, and from what I can tell directly from my screen, daily, is that when a large market cap stock is affected either up big or down big (on news, or whatever event is driving it), it tends to drag the entire sector red, or green, with it. --today's driver seems to be REGN which has a $10 billion market cap and is prob weighted more heavily in these indexes.
It's an ETF/algorithm world now----we just all happen to live in it.
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