October 16th at around 3:59 the price of AMZN dropped $100, then recovered $100 in less than 60 seconds.

Not asking what news event caused this. I believe no news event caused this.

I would like to know what the technicals were that caused this.


  1. Was this just one share holder selling a massive amount in a short timespan?
  2. Did the buyer at that time really randomly get a shares of AMZN $100 dollars cheaper than market value?
  3. Is this considered a mistake? Will someone correct this discrepancy?

enter image description here

  • 3
    Have you checked that there is no problem with the data?
    – Flux
    Oct 17, 2020 at 9:23

1 Answer 1


Most of the time, sharp momentary dips like this is due to bad data. If so, it's usually corrected once the error is recognized. Whether it's bad data or not can be verified by looking at Time & Sales.

With most options and stocks, near the end of the day, the bid/ask spread widens as traders pull their orders and go home. This can begin 10 minutes or so before the close or right at/near the close.

With AMZN, there was no massive EOD volume. The B/A spread widened to as much as $100 at 3:59:59 PM and trades were going off within both prices. It could have been intentional trading at the market or it could have been a fat fingered trade. Anyone who bought at the $100 lower price got a good deal.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .