by Tanta on 9/25/2007 02:49:00 PM

This is unpleasant news (from Bloomberg):

Sept. 25 (Bloomberg) -- Bond insurers, including those owned by AMBAC Financial Group Inc. and FGIC Corp., may need to raise capital to maintain their top credit ratings if losses worsen on subprime mortgage securities, Moody's Investors Service said.

Under what Moody's called its most stressful scenario, losses on securities backed by subprime mortgages could reach 14 percent, causing AMBAC, FGIC, Security Capital Assurance Ltd. and CIFG Assurance North America Inc. to fall short of the capital needed to keep their Aaa ratings. The most likely source of losses would be from guarantees on collateralized debt obligations, which may be backed by subprime mortgage securities. The stress test is higher than Moody's expected loss rate of 10 percent under which the guarantors experience no material losses.

And this is a curious turn of phrase:

``Because ratings are so important to the industry's value proposition, the rating agency believes that a highly rated financial-guarantor with a strong ongoing franchise would likely take whatever action is feasible to preserve its rating during times of stress,'' Moody's analysts led by Stanislas Rouyer in New York wrote in a report released today.

To which industry's "value proposition" are ratings so important? The bond insurers or the CDO managers?