Roosevelt also worked to restrict the power of big business by breaking up a monopoly. In his administration’s first trust-busting case, his attorney general filed suit against the Northern Securities Company, a railroad holding company, for violating the Sherman Antitrust Act, which had not been successfully used against monopolies since its passage in 1890. After this case, though, the Act became an extremely important tool for government regulation of corporations. In 1904, the Supreme Court ordered that the Northern Securities Company be dissolved, a decision that launched a series of antitrust suits. In all, the Roosevelt administration filed forty-three trust-busting suits.