The suit alleges Aledade cheated Medicare out of millions using billing software "rigged" to make patients appear sicker than they were, such as coding anxiety as depression, boosting payments by $3,300 a year per patient.

Conflicts arise when insurers send checks to pay for out-of-network medical services to patients rather than reimbursing a medical provider directly.

"They are constantly looking for new financial tricks and strategies," Cornell University professor Rosemary Batt says.

Although many supporters argue that AARP pursues worthy goals, criticism of its business dealings goes back years.

Nearly $34 billion of that spending came during 2018 and 2019, the latest payment period available.

Eased restrictions on telemedicine during the pandemic have raised concerns that it could inadvertently unleash a wave of billing fraud.

"The days of patients being kept in the dark are over," said CMS Administrator Seema Verma.

Group Health Cooperative in Seattle, is accused of bilking Medicare out of millions of dollars in a federal whistleblower case.