Federal officials offering emergency funding to hospitals, clinics and doctors’ practices have included this stipulation: They cannot foist surprise medical bills on COVID-19 patients.

But buried in the Department of Health and Human Services’ terms and conditions for eligibility is language that could carry much broader implications. It says “HHS broadly views every patient as a possible case of COVID-19,” the guidance states.

Some say that line could disrupt a longtime health care industry practice of balance billing, in which a patient is billed for the difference between what a provider charges and what the insurer pays, a major source of surprise bills ― which can be financially devastating ― for patients. It is banned in several states, though not federally.

For those immersed in the ongoing fight over surprise medical billing, the possibility that HHS might have done with fine print what Congress and the White House could not do with bipartisan support and ample public outrage caught some off-guard and raised questions about what exactly HHS meant.

As the first wave of $30 billion in payouts began to hit bank accounts last week, providers were asked to sign an online form agreeing to the government’s terms. Among those terms is that, “for all care for a possible or actual case of COVID-19,” the provider will not charge patients any more in out-of-pocket costs than they would have if the provider were in-network, or contracted with their insurance company.

The agreement is posted on the HHS.gov page.

“The intent of the terms and conditions was to bar balance billing for actual or presumptive COVID-19,” an HHS spokesperson said late Friday. “We are clarifying this in the terms and conditions.”

Lobbyists, advocates and other experts say the ambiguity could be enough to mandate that providers who accept federal funds have agreed not to send surprise medical bills to patients — whether or not they test positive for COVID-19.

“If you took the broadest interpretation, any of us could be a potential patient,” said Jack Hoadley, a professor emeritus of health policy at Georgetown University and former commissioner of the Medicare Payment Advisory Commission.

Last week, as HHS released an initial draft of its terms and conditions for the emergency funds allocated by Congress in the CARES Act, the Trump administration startled many in health care by declaring that providers would have to agree not to send surprise bills to COVID-19 patients for treatment. A White House spokesperson declined to comment.

But the blanket assertion by health officials that “every patient” is considered a COVID-19 patient, offered without further clarification, seems to go beyond the administration’s announcement and open the door to lawsuits over whether HHS intended to ban balance billing entirely.

“Because the terms and conditions do not appear to be sufficiently clarified, there is a concern that there will be legal challenges around the balance-billing provision,” said Rodney Whitlock, a health policy consultant and former Senate staffer.

Some providers and others in the health care industry have fought tooth and nail to safeguard their control over what they can bill patients for care. Dark-money groups, later revealed to be connected to physician staffing firms owned by profit-driven private equity firms, spent millions last summer to buy political ads targeting members of Congress who were working on legislation to end surprise billing.

Congress has yet to pass any legislation on the matter, but the debate is ongoing behind the scenes. Lawmakers included modest protections against being billed for COVID-19 testing in relief legislation but declined to go further.

Hoadley of Georgetown said HHS’ guidance should address some of the problems that Congress did not account for explicitly in its relief legislation, such as cases of patients being billed for testing for COVID-19 when the test results were negative.

“The providers, the insurers, everybody else is going to need clarification, as well as, of course, all of us as potential patients,” Hoadley said. “That’s going to affect our willingness to” seek testing or treatment, he said.

Frederick Isasi, executive director of Families USA, a nonprofit that advocates for health care consumers, said the group supports the administration’s guidance “wholeheartedly” but urged lawmakers to enshrine broad protections against surprise billing into law.

“It’s time to just ban them permanently, not just related to COVID,” Isasi said, adding: “Families should avail themselves of this as broadly as possible.”

Kaiser Health News (KHN) is a national health policy news service. It is an editorially independent program of the Henry J. Kaiser Family Foundation which is not affiliated with Kaiser Permanente.