A multinational company and two members of the Fortune 500 were named among six insurers found in violation of Medicare marketing rules when federal inspectors checked their books and sat in on presentations as “secret shoppers,” documents show.

All six of the companies checked were found to be breaking the rules in some way, according to a report released this month by the Office of the Inspector General of Health and Human Services. Five of the six plans were faulted for the ways in which they paid sales agents, directly or through field marketing organizations.

Among the six were Aetna Inc., Universal American Corp., and Munich American Holding Corp., which sells Medicare products under the name of Sterling Insurance.

The others were Freedom Health Plans, which operates in Florida; MD Care in California; and Blue Cross and Blue Shield of South Carolina.

Together, the six plans account for seven percent of Medicare Advantage enrollees nationwide. (Editor’s note: The Office of Inspector General had given a higher estimate earlier, but corrected it this afternoon).

Release of the names came as a shock to the plans, according to three that responded to Health News Florida. “We’ve had regular audits and they’ve been perfect,” said Elizabeth Hammond of BCBS-SC. “We’re just baffled.”

Aetna and Freedom say they, too, have very strict oversight over their agents.

Freedom Heath’s Chief Operating Officer Sidd Pagidipati said the company sends its agent-compensation plan to the Centers for Medicare and Medicaid Services (CMS) every year and has heard no objections. “In general, we, as a health plan, are very sensitive to protecting Medicare beneficiaries and their rights. In fact, we have secret shoppers attending 100% of our independent sales seminars.” Anyone who breaks rules goes through immediate retraining or gets fired, he said.

“Aetna is confident that it was fully compliant” with CMS rules on agent commissions, Aetna said in a statement. The company said its staff has concluded after reading the Inspector General’s report that it “does not allege or even suggest that Aetna was not in compliance.”

In fact, the CMS rules on agent compensation are not all that clear, according to the Inspector General’s report. The staff recommended that CMS clarify them; CMS responded that it had already done so during the time the report was being prepared.

CMS spokesman Peter Ashkenaz said the agency is “going through all the data the Inspector General has provided to us to verify or confirm their findings. When we finish that, we will then take action if and where it’s necessary.”

The six companies were among 266 Medicare Advantage plan sponsors that contracted with HHS’s Centers for Medicare and Medicaid Services last year. While the Inspector General chose the six for scrutiny because of past complaints, the report said, there is no reason to suppose that their behavior was vastly different from the rest.

In fact, while auditors and beneficiary-imitators were checking out these six companies, complaints were coming in to CMS about marketing problems with “numerous” others, said Robin Brooks of the Inspector General’s office. The Inspector General’s report pegged that number at 84.

Brooks made the comment in a letter Tuesday sent along with the documents that identified the companies mentioned – but not identified – in the report made public at the beginning of the month. She provided the identities to Health News Florida in response to a request under the Freedom of Information Act.

HNF requested that the identities be released before the open-enrollment and plan-switching season for 2010 closes. Today is the last day; the lock-in period begins April 1 and lasts through Dec. 31. But CMS spokesman Peter Ashkenaz said the agency can open a “special enrollment period” for beneficiaries who have been tricked into signing up for the wrong plan through unfair marketing practices.

The evaluation of the six plans found “gaps in their oversight and a failure to fully implement the regulations” on sales agents, Brooks said in her letter.

A Sept. 2 memo on the project summarizes the key findings:

–Three of the companies that used independent sales agents paid them more than they were allowed to under CMS commission guidelines. They were: Freedom, BCBS of South Carolina, and MD Care.

— Three of the companies made payments to marketing organizations that “may have created inappropriate financial incentives” for agents to steer beneficiaries toward those plans. They were Aetna, Universal American and BCBS of South Carolina.

The only reference to Sterling was in a chart listing plans that had some “unqualified” sales agents. There was no elaboration.

The Inspector General’s staff conducted the evaluation to learn whether the strict new CMS rules governing agents’ pay and marketing behavior that came out in November 2008 were being followed. The rules were created in response to three years of scandals in which some beneficiaries were pressured or tricked into enrolling in high-commission plans or even enrolled without their knowledge.

The title of the report sums up the Inspector General’s staff’s conclusion: “Beneficiaries Remain Vulnerable to Sales Agents’ Marketing of Medicare Advantage Plans.”