What it means: Most people who get their health coverage through the federal government's HealthCare.gov program or a state-based ACA public exchange program have individual or family coverage.

That means ACA exchange enrollment fraud has little direct effect on employer health plan sponsors and their benefits advisors.

But accounts of what happened may provide case studies employers can use to come up with safeguards to prevent enrollment fraud from hurting their own health plans.

The Affordable Care Act public exchange system: Congress developed the ACA public exchange system in an effort to fend off some Democrats who wanted to eliminate private health coverage or to encourage people to sign up for government-run alternatives to private health coverage.

The ACA exchange system lets people buy individual or family coverage written by commercial insurers and managed care companies on a guaranteed-issue basis, without health factors other than age and location used to issue or price coverage.

The enrollees can use income-based government subsidies — federal premium tax credits — to pay for the coverage.

One of the defenses regulators, insurers and exchange program managers developed against underwriting problems was an "annual enrollment period" system.

An annual enrollment period system, or limits on when people can buy coverage without showing what the government classifies as a good excuse to be shopping for coverage, is supposed to limit risk by encouraging relatively young, healthy people to pay for coverage even when they feel great, to avoid the risk that they might be uninsured, and have no way to buy coverage, when they suffer heart attacks or break their legs.

The annual enrollment period has been running from Nov. 1 through about Jan. 15 in many states.

American Indians and Alaska Natives: The ACA includes a provision that exempts American Indians and Alaska Natives from the annual enrollment period rules, and enrollees who qualify for that exemption also get extra help with paying deductibles, co-payments and coinsurance bills.

Alaska regulators discovered in early 2023 that about 100 health plan members there had lied about being Alaska Natives, according to the NAIC's survey summary.

The state has not seen the "AI/AN designation approach" since mid-2023.

A regulator from South Dakota said regulators there have heard some reports about the problem but that the insurers have handled the cases.

A regulator from Montana said it has had a team looking at the issue. "We will have information to contribute," the regulator said, without providing further details.

The Paragon analysis: Paragon is a Washington-based research center that's popular with Republicans. It conducted an influential analysis of ACA exchange plan enrollment fraud in 2024.

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Paragon analysts suggest in a new study that the number of exchange plan enrollees who have lied about their income to get "free" health coverage has increased to 6.4 million this year, up 28% from the total recorded a year earlier.

The analysts say they believe the enrollees lied about their income because the number of uninsured residents in many states who have the right level of income to qualify for "free" coverage — income at 100% to 150% of the federal poverty level — is much smaller than the number of exchange plan users in those states who have told the exchange system that they have income from 100% to 150% of the federal poverty level.

Adding the kinds of application verification rules proposed by the administration of President Donald Trump earlier this year would help, and letting extra COVID-emergency-era premium subsidies expire after 2025 would also help, the Paragon analysts say.

Exchanges now let applicants describe their income without providing tax forms or other documentation, and that should end, the analysts say.