Oh, and I'll beat you to it. Don't even say that this wasn't an internal cross, but an external cross, because you would never find the fill on that 600k+ share trade off an ECN without tanking or making the shares soar. And I don't think you would just have the other half of the trade sitting idly to do the external with on this issue. And in any case, those trades went through the exchange platform, so point is moot.
PS - I love how you prove you are full of sh** by what you post. MMs? Funny. Cross trades are only allowed on exchange traded securities when an asset manager swaps one client's position for another. And even then, the asset manager has to be able to explain why he/she did a cross trade instead of place it over the exchange. As it shows up Nasdaq's official trade list for the day (you can go to the Nasdaq site and check if you would like), then technically, this was not a "cross". I hope you don't quit the day job. Idiot.