More than one million people currently enrolled in Affordable Care Act marketplace plans lack Social Security numbers, a fact that Health and Human Services Secretary Robert F. Kennedy Jr. and Centers for Medicare and Medicaid Services Administrator Dr. Mehmet Oz called "a glaring warning sign for fraud" in a video announcement Saturday from Washington.
The disclosure lands at a moment when Obamacare enrollment has already dropped sharply. After roughly 23.4 million Americans signed up in 2025, according to Kaiser Family Foundation data, the latest HHS figures show an estimated 19.2 million remain on exchange plans. Enhanced subsidies enacted under the Biden administration expired at the end of last year, trimming the rolls. But the fraud question is separate, and, if the administration's numbers hold up, far more damaging to the program's credibility.
Kennedy did not mince words about who he blames for the mess.
"The Obamacare marketplace is plagued by fraud in large part because the Biden administration dismantled basic program integrity guardrails, while partisan lawfare blocked common sense efforts to protect taxpayers."
That charge, that the prior administration deliberately weakened enrollment verification, frames the Trump team's cleanup effort as a matter of basic governance rather than partisan overreach. And the scale of the problem, at least as Kennedy and Oz describe it, is hard to dismiss.
Dr. Oz laid out the alleged mechanics. He said "rogue agents and other bad actors" have been enrolling "unsuspecting Americans in health plans they never signed up for." Those agents, he claimed, then use fake identities to collect fees from insurance companies for "selling plans they never legitimately sold."
The missing Social Security numbers are the clearest paper trail.
"Some of these agents refuse to follow basic rules, like providing their clients' social security numbers. That, my friends, is a huge red flag."
Oz warned anyone involved in the scheme directly. "If you're a fraudster, here's our advice to you: do not walk away from us, run, because we are going to find you," he said.
Kennedy framed the core question in blunter terms: "Why are we paying people we don't know if they actually exist?"
It is a fair question. A Social Security number is the most basic identity check the federal government has. When more than a million enrollees in a taxpayer-subsidized health program lack one, the system is not functioning as a safeguard. It is functioning as a spigot.
Kennedy and Oz described a "zero tolerance policy" for fraud in the Obamacare marketplace. They said the administration has already eliminated "thousands of fraudulent enrollments," though they did not provide a specific number.
Kennedy stated the administration is going further.
"We're also working with insurers to cancel every policy that should never have been issued and recover every taxpayer dollar that was fraudulently paid out."
The cooperation with insurers matters. Insurance companies were, in the scheme Oz described, also victims, paying agent fees for enrollments that were fabricated. Whether those companies cooperate fully, and how quickly fraudulent policies can be unwound, will determine whether the cleanup produces real savings or just press conferences.
The decline from 23.4 million enrollees in 2025 to 19.2 million in the most recent HHS data is significant on its own. The expiration of Biden-era enhanced subsidies accounts for much of that drop. Without the extra federal money, premiums rose, and millions of enrollees either found the plans unaffordable or chose to leave.
But the fraud revelations raise a harder question: how many of those 23.4 million were real enrollees in the first place?
If rogue agents were padding the rolls with fake or unknowing enrollees, people who never sought coverage and never used it, then the Biden-era enrollment highs were partly an illusion. The subsidies were real. The taxpayer costs were real. But some share of the "covered lives" the previous administration touted may have existed only on paper.
The New York Post has previously reported on a government watchdog finding that Obamacare subsidies were granted without documentation to 90 percent of fake test accounts. That earlier finding suggested the marketplace's verification systems were porous long before the current administration began looking.
Kennedy and Oz made strong claims Saturday, but several key details remain unclear. The administration did not disclose the total dollar amount of taxpayer funds it believes were fraudulently paid out. It did not specify how many of the one million enrollees without Social Security numbers are suspected of outright fraud versus those who may have other explanations for missing data. And it did not name any specific enforcement actions taken against identified rogue agents.
The source of the one-million figure itself is not fully transparent. HHS published an enrollment report, but whether the missing-SSN count comes from that report or a separate internal review has not been made clear.
These gaps matter. The administration's case is strongest when it can point to specific canceled policies, specific recovered dollars, and specific agents facing consequences. Broad numbers without granular follow-through risk looking like a political exercise rather than a genuine enforcement campaign.
The Affordable Care Act marketplace was sold to the American public as a system where subsidies would flow to verified, eligible individuals. The entire architecture depends on identity verification. When more than a million people on the rolls cannot be matched to a Social Security number, the architecture has failed, not at the margins, but at its foundation.
Kennedy's accusation that the Biden administration "dismantled basic program integrity guardrails" is a political charge. But the one-million figure, if accurate, is not political. It is administrative. Either the system checked identities or it did not. Either the guardrails existed or they were removed. The number speaks for itself.
The Trump administration now owns the cleanup. Kennedy and Oz have put themselves on the record with specific claims and a specific promise, cancel every fraudulent policy, recover every fraudulent dollar. Taxpayers will be watching to see whether the follow-through matches the announcement.
A health insurance marketplace that cannot verify whether its enrollees exist is not a safety net. It is an invitation.
