S&P Tops Rating Agencies In Busy First Quarter of 2003 Standard & Poor’s led the major rating agencies in subprime business during the first quarter of this year, a new Inside B&C analysis reveals. Through the end of March, S&P rated some $37.44 billion in new subprime securitizations, or 96.2 percent of the period’s $38.92 billion in total issuance. Since the end of last year, S&P’s market share has grown by 3.1 percentage points.