New Records Reveal Problems with Medicare’s AI Prior Authorization Experiment

EFF sued the government back in March for information about the Wasteful and Inappropriate Service Reduction (WISeR) model, a new Medicare program that uses AI to evaluate prior authorization requests for certain medical services. Today, we’re releasing approximately 1,000 pages of records obtained from the Centers for Medicare & Medicaid Services (CMS) through this litigation, including contracts with tech companies, internal status reports and providers’ complaints about the program. The documents (available here) show that WISeR has resulted in widespread delays and denials of care, operational chaos, and reports of patient harm.

Why We Sued for Records about WISeR

EFF filed the FOIA lawsuit to gain badly needed transparency into an experimental AI program that could jeopardize Medicare beneficiaries' access to care. In January 2026, CMS launched the WISeR model, subjecting seniors in six states to AI-driven prior authorization decisions. Medical providers must now request permission before delivering certain medical treatments if they want assurance that Medicare will cover them. Private companies contracted by CMS evaluate the requests using AI. In the absence of rigorous safeguards, AI-driven prior authorization determinations can lead to unwarranted—and even discriminatory—delays or denials of necessary medical care. 

Little is known about the AI systems that WISeR vendors are using to process prior authorization requests. Although CMS says that a qualified human clinician must review all denials, research has shown that AI-generated recommendations often influence human decisions. And the design of the WISeR program creates a financial incentive for vendors to deny care, since they are paid for averted expenditures. Just months after the program launched, medical providers reported improper denials, administrative friction, and lengthy delays that have left patients waiting in pain.

EFF’s FOIA request sought records pertaining to the CMS contracts with WISeR software vendors; any tests for accuracy, bias, or hallucinations in vendors' technology; and any audits, monitoring, or evaluation of WISeR and participating vendors.

CMS Documents Highlight Issues with the WISeR Model

CMS records obtained by EFF echo issues that medical providers, patient advocates, and lawmakers have warned about since WISeR began. This includes long wait times, rampant technical failures, inappropriate denials, and harm to patients.

Delayed Responses to Prior Authorization Requests

CMS publicly states that WISeR vendors should respond to prior authorization requests within 72 hours, but records received by EFF show widespread delays. Internal status reports from the first few months of the program show that WISeR vendors failed to respond within 72 hours for a significant number of requests. One status report cites a prior authorization request that went unanswered for 83 days ("WISeR FOIA Response - Combined Records," page 234). These delayed responses can have serious consequences for patients. Medical providers reported that WISeR has delayed medically necessary care and left patients in pain as they waited for approvals.

Payment Methodology Provides Financial Incentive to Deny Care 

The released records confirm that WISeR’s payment methodology creates a financial incentive to deny care. Specifically, WISeR vendors are paid for requests that they deny (though not for denials reversed on appeal). This profit motive aggravates the risk that AI-assisted decision-making may unfairly deprive people of the services they need.

CMS publicly claims that it safeguards against inappropriate denials by tying vendors’ payment rates to “quality scores,” which reflect the timeliness and accuracy of vendors’ decisions. However, the recently released WISeR Data Reporting Guide shows that low quality scores reduce payments by only 5-10%.

WISeR Vendors Have Denied Thousands of Prior Authorization Requests

Documents obtained by EFF appear to support reports that WISeR vendors may be denying claims at unusually high rates. Two companies alone denied over 20,000 prior authorization requests in the first 3 months of the program. One company, Virtix, the vendor that CMS required to submit a Corrective Action Plan, denied more requests than it approved during this time period.

Medical Provider Feedback Ties WISeR Delays to Patient Harm

Feedback from medical providers emphasize that WISeR delays have harmed patients. The released records include March 2026 responses to a feedback form about Innovaccer, the WISeR vendor processing requests for Ohio. Medical providers complained about a lack of communication, administrative issues, and long response times. Several responses emphasize that long response times from the WISeR vendor harmed patients ("WISeR FOIA Response - Feedback Survey Responses"):

“We have patients calling our offices crying in pain because their procedures are being delayed while awaiting approvals or guidance tied to this model. A 3–4 day delay for necessary pain procedures is already difficult for vulnerable patients, but when providers cannot obtain answers for weeks, the situation becomes unacceptable.”

“I HAVE HAD TO WATCH 3 PATIENTS CRY AT BEDSIDE FOR NOT HEARING BACK ON THEIR PRIOR AUTH FOR KYPHOPLASTY/VERTABRAL AUGMENTIATION PROCEDURE. THESE PATIENTS ARE IN DEEP PAIN.”

“I have had cases submitted and waiting over 1 1/2 months for a UTN to be generated… In the meantime patients are having to be cancelled for surgeries they need. This is not acceptable they are severely hindering patient care.”

Rushed Rollout Amidst Widespread Technical Failures 

CMS WISeR launched in January 2026, just six months after it was announced. Despite warnings from both medical providers and a vendor about insufficient preparation time, CMS chose not to delay the launch. 

Approximately a month before the launch, one of the vendors, Innovaccer, alerted CMS that it intended to go live with a version of its software that lacked full functionality and had not been fully tested. It cited several barriers to going live with full functionality, including changing requirements and expectations, unclear governance processes, and lack of time for end-to-end testing with the provider community ("WISeR FOIA Response - Combined Records,", page 216-217). Innovaccer said it would auto-affirm all prior authorization requests until it could develop full functionality and explained that “Given CMS's decision not to delay the model start date, auto-affirming is the only path available” ("WISeR FOIA Response - Combined Records," page 217).

Innovaccer had not yet finished developing or testing some features several months into the program, according to an April 2026 status report. Innovaccer was not the only vendor who faced technical challenges before and after WISeR launched. Weekly status reports and provider feedback in the released records show widespread challenges associated with WISeR’s rushed rollout (for example, "WISeR FOIA Response - Combined Records," pages 238 and 383).

More Urgent Medical Services Considered for Inclusion in Future Years of WISeR Model

In its first year, the WISeR model introduced prior authorization requirements for a set of 13 medical services. The June 2025 Innovation Center Investment Plan for WISeR lists medical services that could be added to the program in future years. This planning document considers the possibility of adding services “where prior authorization would have to be done on a more urgent or emergent basis,” including air ambulance transport, cancer treatment, MRI scans, and medications without publicly available coverage criteria.

More Transparency is Needed About Medicare’s AI Experiment

CMS continues to produce records in response to EFF’s lawsuit. Records released thus far echo concerns that providers have raised since WISeR launched, including long delays, financial incentives to deny care, and technical problems. But important questions remain about the AI systems private companies are using to inform decisions about whether to provide people with Medicare benefits. As CMS continues to produce documents, we will continue to make them available to the public. The public deserves to know how AI is driving decisions that affect patients’ access to care.