This stock did not go up because people thought it was a great buy. I have seen this happen before and the reason why bankrupt companies go up is due to short covering. Anyone following GNK knew they were in trouble a long time ago . There were over 14 million shares shorted as of March 15 probably more before today so anyone short does not want to hold through a bankruptcy procedure, you usually cover the long -term short position and maybe go to a short -term short because you know it is going to zero.
Last year there was a stock called Orchard supply and the same thing happened. That one got so bad the exchange forced management to put out a release saying basically the companies' shares are worth zero it took some time but eventually the stock got crushed, expect the same here. No one really knows the timing of bankruptcies, they can pull the plug at any time depending on court schedules etc....
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