One of the most publicized of the bond insurance bears was William Ackman of Pershing Square Capital Management, who pressed his case in part with presentations given over the Internet. He received lots of press, and by some measures seems to be winning, especially when it comes to MBIA (which reported another loss and another writedown--this one for $3.6 billion). Before that, the company already had taken $3.7 billion on writedowns for last year. According to HedgeFund.net, Ackman expects the company to ultimately writedown $11 billion on structured credit products. At some point, you would think the shorts would bail. Indeed, the stock got a little goose Monday. Time for a big decision in general for a lot of shorts.  

For more:
- here's the article [1]

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