liqudity put of CDO

--When the credit crunch intensified in the summer, demand for CDOs dried up. Consequently, banks that arranged CDOs got stuck with subprime assets they had intended to eventually place in CDO entities. In addition, as underwriters of the deals, some were also left with large amounts of CDO bonds they could no longer sell. In both cases, the CDO assets and debt were already on a bank's balance sheet. --But in some cases, banks were suddenly forced to take large amounts of fresh CDO debt onto their balance sheet. --Here's how. Some CDO trusts funded themselves by repeatedly selling short-term debt into the markets. When the debt became due after, say, three months, it was supposed to be re-sold to investors, or in market jargon, it would be "rolled over." --In the summer, with the credit crisis deepening, investors had no desire to keep buying any short-term debt issued by CDO trusts. But some banks, in trying to make their CDO deals more attractive to investors, had committed to buy that short-term debt if it couldn't be rolled over. Citigroup called that commitment a 'liquidity put,' when explaining why it ended up taking $25 billion of CDO debt onto its books.