I don't think any of the other MM's have shares to give up, so they are probably struggling to maintain liquidity here. Instead of pushing the price up, though, they can only short sell shares, so they try to keep pressure down. They most likely have a large naked short position that needs filled, and since this stock has been running strongly up for so long, they are assuming it will drop any time now so they can fill their positions. So they short the hell out of it. Small share block buys seems to be working, when the walls aren't real. Kills the short game fast.
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