The Supreme Court won't hear an appeal from shareholders who claim the Standard & Poor's ratings firm made false statements about its ratings of risky mortgage investments that helped trigger the financial crisis.

The justices on Monday let stand a lower court ruling that threw out a lawsuit filed by the Boca Raton Firefighters & Police Pension Fund against S&P's parent company, McGraw-Hill.

A federal appeals court ruled 2-1 that statements about the integrity and credibility of S&P's credit ratings used routine, generic language that did not mislead investors.

The shareholders argued that false statements regarding a central aspect of the company's business were enough to violate federal securities laws.