They were selling ratings on bonds instead of doing what they're actually supposed to do, which is evaluate the bond on it's merits and then assign it a rating.

It was pay-for-ratings instead of pay-for-evaluation.

This is documented pretty well in Michael Lewis' and Matt Taibbi's books about the 2008 financial crash.

Their involvement in the 2008 crash certainly didn't win them any admirers. Not sure if gp has something else in mind though.