Yes, the trustee is using 4 exchanges to get rid of the BTC, and got rid of a quarter of the 200,000 bitcoins so far. Which leaves another 150,000 bitcoins that are going to be dumped in the market. As this is a liquidation of the MT. Gox exchange(Japan), this has to be done as fast as possible to resolve the whole liquidation process. This does have a huge effect on the market and prices, as these bitcoins are sold off in huge amounts.