Trding, It hasn't been just after videos or presentations, it's been happening for months. This underbidding of the ASK is CDEL, NITE, ETR & CSTI and even today it's a bit more pronounced except for one trade (EDIT which could have been your's) that hit the ask and went through as a buy.

Yes, there are buys but some people will put in a limit order just over the bid price and if there is a few trades above it and below it, that limit trade can get filled.

GLTU

HCIT