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BlackRock (BLK), State Street (STT) and Vanguard Group have been accused by authorities in Texas and nearly a dozen other states of using their investments in coal mining and utility companies to manipulate electricity prices.

Led by Texas Attorney General Ken Paxton, the states accuse the three money managers of pressuring coal companies to "deliberately and artificially constrict" supply, resulting in higher prices and producing "extraordinary revenue gains" for their investments. The plaintiffs also accuse the companies of violating federal and state antitrust law barring shareholders from using their positions as investors to block potential competition.

Joining Paxton in the suit filed Wednesday in federal court in Tyler, Texas, were attorneys general from 10 other states, including Alabama, Arkansas, Indiana, Iowa, Kansas, Missouri, Montana, Nebraska, West Virginia and Wyoming.

BlackRock, State Street and Vanguard did not immediately reply to requests for comment from MT Newswires on Wednesday.

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