8 times normal volume, BEAT down about 12%, no news.
Maybe just another day at the office for small medical-ish companies. T2Biosystems, Aethlon Medical, Abeona Therapeutics, Akari Therapeutics, Imununomedics. !!!. Some up 100%+, others crushed on the day.
KC
I could find no news for the drop. This is my analysis:
Over 80,000 shares were sold at the open, about 20% of the average daily volume. That could have triggered a bunch of stop loss orders. These, in turn, as they drop the price further, trigger more stop loss orders in a chain reaction until they run out of fuel (stop loss orders). BEAT had a similar gap down in early May.
I took the opportunity to buy back my covered calls for a nice profit. I had sold one the day before making a 50% profit on the premium overnight! Not much money but fun nonetheless. 
At $32.70 BEAT is 15% off the all time high of September 8. Maybe it’s time to add…
Denny Schlesinger
This is a very small position for me. Ii’m thinking it was less than 1%. I bought more in the first hour or so (bedtime here)after finding no news. I was thinking the same as you. Those little algorithms, seem so easy to stampede the herd. We’ll see if the cowpokes can get 'em to bed down.
KC
Here is the “news.” Off Wall Street put a sell rating on the stock on Friday. Other analysts all have buy ratings
https://www.dispatchtribunal.com/2017/09/15/biotelemetry-inc…
I had never heard of Off Wall Street. Here is what they say about themselves
Founded in 1990, Off Wall Street is the leading U.S. independent research provider of sell/sell short recommendations for professional money managers. Off Wall Street has a track record that is unmatched among its peers.
http://www.offwallstreet.com/who-we-serve/
Another Citron?
I added this morning.
Denny Schlesinger