If someone's finally giving up and dumping out, not interesting, but if someone's trying to scare others (several stubborn nutheads) to give up and make them dump, then interesting. For the latter case, why would someone do that, I have no plausible explanation.
If someone were dumping 500,000 shares on the market why would the first two trades go off at the lowest price of the day?
Looks to me like that someone stepped in and purchased 500,000 shares, paying the lowest price for shares at the cheapest price available on the first two trades.