Moody's Investors Service, often referred to as Moody's, is the bond credit rating business of Moody's Corporation, representing the company's traditional line of business and its historical name. Moody's Investors Service provides international financial research on bonds issued by commercial and government entities. Moody's, along with Standard & Poor's and Fitch Group, is considered one of the Big Three credit rating agencies. It is also included in the Fortune 500 list of 2021. The company ranks the creditworthiness of borrowers using a standardized ratings scale which measures expected investor loss in the event of default. Moody's Investors Service rates debt securities in several bond market segments. These include government, municipal and corporate bonds; managed investments such as money market funds and fixed-income funds; financial institutions including banks and non-bank finance companies; and asset classes in structured finance. In Moody's Investors Service's ratings system, securities are assigned a rating from Aaa to C, with Aaa being the highest quality and C the lowest quality. Moody's was founded by John Moody in 1909 to produce manuals of statistics related to stocks and bonds and bond ratings. In 1975, the company was identified as a Nationally Recognized Statistical Rating Organization (NRSRO) by the U.S. Securities and Exchange Commission. Following several decades of ownership by Dun & Bradstreet, Moody's Investors Service became a separate company in 2000. Moody's Corporation was established as a holding company. Role in capital markets Together, they are sometimes referred to as the Big Three credit rating agencies. While credit rating agencies are sometimes viewed as interchangeable, Moody's, S&P and Fitch in fact rate bonds differently; for example, S&P and Fitch Ratings measure the probability that a security will default, while Moody's ratings seek to measure the expected losses in the event of a default. All three operate worldwide, maintaining offices on six continents, and rating tens of trillions of dollars in securities. However, only Moody's Corporation is a free-standing company. Moody's Investors Service and its close competitors play a key role in global capital markets as three supplementary credit analysis provider for banks and other financial institutions in assessing the credit risk of particular securities. This form of third party analysis is particularly useful for smaller and less sophisticated investors, as well as for all investors to use as an external comparison for their own judgments. Credit rating agencies also play an important role in the laws and regulations