MORGANTOWN, W.Va. (AP) â¿¿ Attorneys for Massey Energy now have until June 18 to formally respond in court to shareholders who say they were deliberately misled about the coal company's safety record.

The parties agreed to the new deadline in a filing in U.S. District Court in Beckley. Judge Irene Berger recently rejected Massey's motion to dismiss the case.

Institutional shareholders led by the Massachusetts Pension Reserves Investment Trust say Massey lied about its safety record before the Upper Big Branch mine disaster killed 29 West Virginia miners in April 2010.

Only after the worst U.S. mining disaster in four decades did the shareholders learn the extent of the company's problems.

They argue that corporate deception artificially inflated stock prices between 2008 and 2010.

Massey has since been bought by Virginia-based Alpha Natural Resources Inc.

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