A judge incorrectly dismissed several insurance companies from a lawsuit accusing insurers of overbilling the federal government for Hurricane Katrina's flood damage in Louisiana, a federal appeals court has ruled.

Wednesday's ruling by the 5th Circuit Court of Appeals in New Orleans only revives part of the case that lawyers for a group of purported "whistleblowers" filed against eight insurers and six adjusting firms after the August 2005 storm.

A three-judge panel from the appeals court upheld a lower court's ruling that Allstate Insurance Co. and State Farm Fire and Casualty Co. must be dismissed from the Louisiana lawsuit because they already were defendants in a similar suit in Mississippi.

However, the 5th Circuit said U.S. District Judge Peter Beer erred in dismissing the other insurers and adjusting firms that aren't named in the Mississippi case.

Other defendants in the Louisiana case include Liberty Mutual Fire Insurance Co., Fidelity National Insurance Co., American National Property & Casualty Co., American Reliable Insurance Co., and Standard Fire Insurance Co.