In the mid-1990s, the U.S. Justice Department's antitrust division opened an investigation to determine whether unsolicited ratings amounted to an illegal exercise of market power, however the investigation was closed with no antitrust charges filed. Moody's has pointed out that it has assigned unsolicited ratings since 1909, and that such ratings are the market's "best defense against rating shopping" by issuers. In November 1999, Moody's announced it would begin identifying which ratings were unsolicited as part of a general move toward greater transparency. The agency faced a similar complaint in the mid-2000s from Hannover Re, a German insurer that lost $175 million in market value when its bonds were lowered to "junk" status. In 2005, unsolicited ratings were at the center of a subpoena by the New York Attorney General's office under Eliot Spitzer, but again no charges were filed.