And it probably involves lent money (even if it started before all the money was lent).
Money was lent after the initial pump happened. Shorts only went up by a couple hundred BTC (Short is a good call IMO) after the pump.
Either the new longs are underwater already, or it was just borrowed and never used. If this is the case, then it might be to entice stop hunters to sell into Mr. Acummulator and co's bids.