Source: Congressional Inquiry Announcement, August 2025; Coverage by Reuters and Policy Watchdog Reports

Washington, D.C. August 12, 2025 - Senator Chuck Grassley (R-Iowa) has launched an investigation into UnitedHealth Group, raising concerns that the insurer may be inflating Medicare Advantage billing practices for financial gain. At the heart of the inquiry is whether diagnoses reflect actual patient health conditions or are being recorded primarily to increase reimbursements from the Centers for Medicare & Medicaid Services (CMS).

Medicare Advantage Under Scrutiny

Medicare Advantage now covers more than 50% of all Medicare beneficiaries, using risk adjustment payments that provide higher reimbursements for patients with severe or complex conditions. However, watchdog groups and federal auditors have long warned the system is open to abuse.

Some insurers, they claim, rely on limited encounters such as home health assessments to record high-severity diagnoses—conditions that may not be confirmed through in-person medical exams.

“Taxpayers deserve to know whether these billing practices are padding corporate profits at Medicare’s expense,” Grassley said in his announcement. “We need transparency and accountability to protect seniors and the program they depend on.”

Background of the Inquiry

The probe builds on years of scrutiny into upcoding practices in Medicare Advantage. Federal agencies, including the U.S. Department of Justice (DOJ) and the Office of Inspector General (OIG), have previously taken enforcement actions against multiple insurers accused of overbilling through exaggerated risk coding.

UnitedHealth, one of the largest players in the Medicare Advantage market, has faced similar allegations in past government investigations.

UnitedHealth’s Response

In a statement, UnitedHealth Group defended its billing practices, stating that its coding “aligns with CMS guidelines and accurately represents patient health.” The company confirmed it is fully cooperating with Grassley’s office and remains committed to delivering high-quality, compliant care for Medicare beneficiaries.

Potential Policy Reforms

Health policy experts note that Grassley’s inquiry could pave the way for legislative reforms to Medicare Advantage billing. One proposal gaining traction would limit the use of diagnoses from home assessments unless verified in a clinical setting. Such reforms could reshape how risk adjustment payments are calculated, with major implications for insurers, providers, and patients.