The race for market share in the subprime MBS rating business heated up in the second quarter. While Standard & Poor’s remained atop the market, its lead has narrowed significantly, a new Inside B&C Lending analysis reveals. S&P clearly remained the dominant player in the market during the first half of the year, rating 95.6 percent of the $241.21 billion in subprime MBS issued during the period. But the firm – which has been… [One data table included]