With borrowing costs at their lowest levels since 2004, reinsurers are loading up on corporate debt in part to fund stock buybacks. The latest tally, according to Bloomberg News, is $1.34 billion in additional borrowing, with Endurance Specialty Holdings (ENH), a Bermuda-based company, recently selling $85 million in bonds. Other recent transactions include Axis Capital Holdings (AXS) and PartnerRe (PRE) each issuing $500 million in bonds and RenaissanceRe (RNR) adding $250 million to the count.

After weeks of speculation, the financial damage from the Chile earthquake and Windstorm Xynthia in Europe is starting to emerge. According to a recent report by Moody's, 16 global reinsurance companies have reported their net insured losses (before taxes) from the catastrophe event, and the damage has already reached $3.5 billion, increasing an already high tally. The firm expects these events to have a noticeable impact on first quarter results for the industry.

According to the report, the first quarter of 2010's results "will have many moving pieces, including the possibility of favorable loss reserve development." It continues, though, that "we would expect a number of reinsurers to post both operating and net losses for the quarter."

In what surely must be the PR move of the decade, Moody's Corp. (NYSE: MCO) has downgraded Berkshire Hathaway (NYSE: BRK.A) from AAA to AA2.

Why is this a great PR move? Well, Berkshire owns 20% of Moody's. And what could be a better demonstration of Moody's independence and objectivity than its decision to downgrade the financial strength of its biggest shareholder?

Pretty clever, no? Sure -- unless you start to consider that Moody's and the other ratings agencies gorged on fees from investment banks to rate toxic waste for years -- using their AAA credit ratings to convince investors to buy the securities. Now that the ratings agencies have no fees to earn from rating toxic waste, they are studiously trying to rebuild their reputation for objectivity.

Bloomberg News reports that Moody's (NYSE: MCO) may downgrade municipal bond insurer MBIA (NYSE: MBI) after it reported deepening losses from the mortgage-market slump. MBIA's insurance financial strength rating may fall to the Aa range, although a drop to the A category is possible. MBIA's stock is down 91% since the end of May 2007.

That's when I first suggested that investors consider selling MBIA shares short. William Ackman had already shorted MBIA because he thought it lacked the capital needed to support its obligations. Back then, MBIA traded at $66.59 a share -- today it's down to $5.88. His bet proved prescient.

Meanwhile, investors are wagering that MBIA won't make it. Credit-default swaps tied to MBIA's insurance unit rose to a record as investors hedged against the risk the company's guarantees will sour. Sellers of five-year contracts demanded 23% upfront and 5% a year. That's up from 18.5% initially and 5% a year yesterday.

Only $5.88 more to go.

Peter Cohan is President of Peter S. Cohan & Associates. He also teaches management at Babson College and edits The Cohan Letter. He has no financial interest in MBIA securities.

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