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May 21 (Reuters) - A U.S. judge has allowed a group of BPPlc shareholders to pursue a class-action lawsuitaccusing the company of misleading them by understating theseverity of the 2010 Gulf of Mexico oil spill.
U.S. District Judge Keith Ellison in Houston also deniedclass certification to a second group of shareholders thatclaimed BP had, prior to the explosion of the Deepwater Horizondrilling rig, overstated its ability to manage safety issues.
Ellison's decision on Tuesday could add to BP's clean-up andlitigation costs for the spill. BP said this week it has alreadytaken a $42.7 billion pre-tax charge.
It can be easier for investors to recover more money atlower cost by suing as a group.
The judge said investors who bought BP's American depositoryshares shortly after the April 20, 2010 spill may pursue claimsas a group that BP publicly "lowballed" the oil flow rate soonafter the rig explosion, and that the share price "did notreflect the magnitude of the disaster facing the company."
BP did not immediately respond on Wednesday to requests forcomment. Steven Toll, a lawyer for the plaintiffs, did notimmediately respond to similar requests.
The case is In re: BP Plc Securities Litigation, U.S.District Court, Southern District of Texas, No. 10-md-02185. (Reporting by Jonathan Stempel in New York; Editing byBernadette Baum)
