Usually, it’s illegal for employers to ask you to fork over your private medical information, which protects you from discrimination based on a medical condition or disability. But new so-called wellness programs, aimed at curbing healthcare costs among employees, are making it harder and harder for employees not to give up that sensitive info. Some organizations, like AARP, an advocacy group for older Americans, say the practice has now crossed a line.

On Monday, AARP filed a lawsuit against the federal agency that sets the rules for those wellness programs, the US Equal Employment Opportunity Commission (EEOC). The suit argues that new rules set to take effect in 2017 will violate the anti-discrimination laws that protect the privacy of medical information because they set incentives to participate in the programs too high. That is, employees that don’t want to reveal their medical history could potentially miss out on thousands of dollars in health insurance deals—money some employees may not be able to refuse for personal financial reasons.

Thus, AARP members “face imminent harm flowing directly from the rules because the rules will cause them to either incur significant financial penalties or divulge… protected health and genetic information when they do not wish to do so,” the suit reads. “That information, once revealed, will never be confidential again.”

The AARP is seeking a preliminary injunction on the new rules, which the EEOC issued in May. More specifically, the rules would allow employers to cut annual health insurance premiums by up to 30 percent for individuals and 60 percent for couples if they participate in the wellness programs. Such programs, which are growing in popularity among employers, may simply help employees stop smoking or exercise more. But others may include comprehensive medical surveys and routine tests that monitor employees’ cholesterol, diabetes, weight loss, or other conditions and metrics. Proponents and the Obama administration argue that the goal is for the programs to lower healthcare costs across the board by improving the health of the workforce. If an employee buys into that idea and is paying the average 2016 annual premium of $6,435 (according to the Kaiser Family Foundation), he or she could save $1,930.50 with the 30-percent discount incentive.

The AARP argues that such a discount amounts to a penalty to those who don’t want to participate in wellness programs and undercuts the legal requirement that employees participate voluntarily. In turn, the health and genetic information collected through the programs’ medical questionnaires and testing could open the door to discrimination and stigma—both blatant and subtle—something Congress expressly intended to prevent, the lawsuit argues.

Critics of the lawsuit argue that those fears of stigma and discrimination based on medical conditions are unfounded. “There’s no evidence of these things happening,” James Gelfand, a senior vice president for the Erisa Industry Committee, a trade group representing employers, told The New York Times.

However, the EEOC has taken legal action against companies for allegedly discriminating against employees who resist participating in wellness programs. In September, a federal court ruled partly in favor of the EEOC, which claimed that Orion Energy Systems discriminated against an employee who refused to submit to medical testing as part of the company’s wellness program. The employee said that Orion forced her to pay 100 percent of the employer-provided health insurance premium and later fired her because of her refusal. The court ruled that participation in the wellness program was voluntary.

In 2014, the EEOC tried to stop Honeywell International from fining employees and their spouses up to $4,000 each (from surcharges and lost contributions) for not participating in a wellness program survey.

"If they don't get the survey, then they have to pay $100 more per month for their policy," Honeywell CEO David Cote told CNBC at the time. "So we don't refuse anybody any coverage. And the whole point is, why should people who don't care about how they're living, why should they be able to take advantage of all the people who do care?"

The federal court in Minnesota dismissed EEOC’s bid for an injunction on Honeywell’s policy.

In this week’s lawsuit, AARP notes the EEOC’s past efforts to protect employees and their medical privacy. The new rules “depart starkly from the EEOC’s longstanding position,” the lawsuit reads. However, the EEOC is stuck in a legal quagmire of trying to uphold anti-discrimination laws while also abiding by the Affordable Care Act, which allows employers to use financial incentives to goad people into wellness programs.

According to a 2016 employer health benefits survey by Kaiser, 83 percent of large employers (200 employees or more) now offer some sort of wellness program. Nearly 60 percent of businesses have a program that includes in-depth medical surveys and assessments. Of those businesses, 54 percent use financial incentives. Fifty-three percent of all businesses reported having programs that included biometric testing, which measures employees’ health risk factors, “such as body weight, cholesterol, blood pressure, stress, and nutrition.” Of the businesses using biometrics, 59 percent offer incentives in the way of discounts, cash, or merchandise. Some of those incentives are tied to successful health outcomes, like weight loss or lowered cholesterol.