A federal judge ordered Anadarko Petroleum Corp, which owned part of the blown out well at the center of the 2010 Gulf of Mexico oil spill, to face a lawsuit accusing it of defrauding shareholders, but significantly narrowed the plaintiffs’ case.

U.S. District Judge Keith Ellison in Houston said that while shareholders had highlighted 28 allegedly misleading statements attributable to Anadarko, they were entitled to sue over only a single “isolated” statement concerning the Macondo well, the majority of which was owned by BP Plc.

That statement was made by Anadarko senior vice president Robert Daniels on a May 4, 2010, earnings conference call, two weeks after the blowout, when he said Anadarko had not been involved in the design of or procedures at the well.

“The well design and procedures, operations procedures were all done before we actually farmed in,” he told a caller, according to Ellison’s decision on Monday. “We were not involved in that at all on this well.”

Shareholders had accused Anadarko of mismanaging its 25 percent stake in the Macondo well, and understating its ability to manage risk and handle liabilities.

Ellison said one could make a “compelling” inference that Daniels “simply misspoke” and was not trying to blunt the impact of the spill on Anadarko’s share price, but that his directness could offer a “cogent and compelling” inference to the contrary.

In rejecting other allegations, Ellison concluded that many alleged misleading statements were too general or “squishy” to provide a basis for securities fraud claims against the Houston-based oil and gas exploration company.

Anadarko spokesman John Christiansen said the company was reviewing the decision. It had sought to dismiss the lawsuit.

Gerald Silk, a lawyer for the plaintiffs, did not immediately respond to a request for comment.

The lead plaintiffs are the Pension Trust Fund for Operating Engineers in Alameda, California, and the Employees’ Retirement System of the Government of the Virgin Islands.

In February 2012, Ellison allowed BP shareholders to pursue their own civil fraud lawsuit against that company, but limited the case to investors who had bought BP’s American depositary receipts on U.S. exchanges. BP has denied fraud.

The explosion of the Deepwater Horizon drilling rig and Macondo well blowout killed 11 people.

The case is In re: Anadarko Petroleum Corp Class Action Litigation, U.S. District Court, Southern District of Texas, No. 12-00900.