The US shale giant is selling 427,000 net acres in North Dakota and Montana after admitting that the geological concept behind its leasing push in 2010 to 2011 was flawed, and stating that it does not have the time or money to prove up secondary targets, according to sales documents seen by ­Upstream.

The acreage is concentrated in Stark and Hettinger counties, where the company holds 175,800 and 100,600 acres respectively.

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