Eighty-nine investors defrauded by now-imprisoned Houston financier Robert Allen Stanford want $115 million from seven insurance companies in addition to claims that could total as much as $1 billion against the Louisiana Office of Financial Institutions and SEI Investments Co.

But six of the insurers responded Monday by transferring the investors’ 4-year-old state court suit to Baton Rouge federal court, action the investors have fought hard in the past.

“We feel confident that this case should not be removed to federal court, because the state court has already ruled on it” and granted the investors class-action status, said Phillip W. Preis, Baton Rouge attorney for the investors.

Telephone and email requests for comment from three New Orleans attorneys for the insurance companies were not returned.

The investors sued OFI and Pennsylvania-based SEI in 19th Judicial District Court in Baton Rouge in 2009. That was soon after the Securities and Exchange Commission shut down Stanford’s worldwide operations and alleged his investment program was nothing more than a fraudulent scheme.

But a federal judge in Dallas, where the SEC had filed its complaint, yanked the Louisiana investors’ suit into his Texas court and then dismissed the case.

The Dallas judge ruled in 2011 that the Baton Rouge investors suit violated a Securities Litigation Uniform Standards Act prohibition against state court litigation that could negatively affect the nation’s financial markets.

Last year, however, a three-judge panel of the U.S. 5th Circuit Court of Appeals overruled the Dallas judge and concluded that investors could pursue recovery of their losses in Baton Rouge state court.

That returned the investor claims to state District Judge Michael Caldwell, who held hearings on disputed allegations that OFI knew of Stanford’s misdeeds and should have warned investors, as well as a complaint that SEI ignored a duty to tell investors that Stanford’s assets were grossly overvalued. SEI’s services were contracted by Stanford.

Caldwell issued a judgment last year that certified the investors’ suit as a class action, meaning that all people who lost investments at Stanford Trust Co.’s Baton Rouge office could join the suit as plaintiffs against SEI, OFI and now SEI’s seven insurers.

Caldwell has not yet scheduled a trial for the case.

The U.S. Supreme Court has agreed to hear arguments on appeals of related Stanford investor cases in October.

In Baton Rouge, attorneys for both SEI and OFI repeatedly have denied all allegations that their clients failed any responsibility to alert investors about Stanford’s frauds.

“The role of the OFI is to regulate, not to ensure that those who invest in companies subject to OFI regulation will never lose money as a result of criminal behavior,” OFI attorney David Latham told Caldwell in one court filing.

“SEI did not make any false statements” to Stanford investors, SEI attorney J. Gordon Cooney Jr. told Caldwell in September. Cooney later added: “SEI has not violated Louisiana securities law.”

Court records show the investors added SEI’s insurers to its list of defendants in an amended complaint that was filed Feb. 13 under seal.

Preis said Monday the amended complaint was filed under a nonpublic seal because it contains information related to OFI’s exam reports on Stanford Trust, which Caldwell ruled earlier must remain confidential.

The six insurers that transferred the dispute Monday to U.S. District Judge James J. Brady are Allied World Assurance Co. (U.S.) Inc., Continental Casualty Co., Arch Insurance Co., Indian Harbor Insurance Co., Nutmeg Insurance Co. and certain underwriters at Lloyd’s of London.

Those insurers told Brady a seventh firm — Endurance Specialty Insurance Ltd., of Bermuda — did not join their motion because Endurance officials had not yet been served with a copy of the investors’ suit.

Stanford has been in federal custody since June 2009, when he was indicted by a federal grand jury in Houston for worldwide frauds alleged to exceed $7 billion. He was convicted on fraud charges last year and sentenced to a prison term of 115 years.