A coalition of state officials demanded that Standard & Poor's remove ten companies from the S&P 500 because all ten have moved their legal addresses to locations considered offshore tax havens.

The coalition is led by led by California Treasurer Phil Angelides and backed by the state treasurers of Connecticut, Maine, Massachusetts, Wyoming, Kentucky, Colorado, Oregon, Iowa, and the comptroller-elect of New York.

The companies named in the request are Schlumberger, Carnival Corporation, Transocean Inc., McDermott International, Noble Drilling Corporation, Cooper Industries, XL Capital Ltd., Ace Limited, Tyco International and Ingersoll-Rand.

The move follows the introduction of shareholder resolutions last month at Tyco, Ingersoll-Rand and McDermott, demanding that the companies return their legal headquarters to the U.S. The resolutions were co-sponsored by CalPERS (California Public Employees Retirement System) and supported by the California State Teachers Retirement System.

S&P spokeswoman Rebecca Hill said that it will resist the pressure to delist the ten firms. "We believe these companies are leading companies in the U.S. market, and it would be a disservice to investors if these companies were to be excluded." She said, however, that S&P will examine the request later.