Credit rating agencies and the subprime crisis

Credit rating agencies (CRAs), firms which rate debt instruments/securities according to the debtor's ability to pay lenders back, played a significant role at various stages in the American subprime mortgage crisis of 2007–2008 that led to the 2008 financial crisis and the Great Recession of 2008–2009. The new, complex securities of "structured finance" used to finance subprime mortgages could not have been sold without ratings by the "Big Three" rating agencies—Moody's Investors Service, Standard & Poor's, and Fitch Ratings.

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