An Alaska rheumatologist and her husband have pleaded guilty in a $12.5 million healthcare fraud scheme that included underdosing or treating patients with expired medicines, overcharging insurance companies, and evading nearly $4 million in taxes, according to a press release from the US Attorney’s Office, District of Alaska.

Claribel Tan, MD, 61, and her husband, Daniel Tan, 70, operated a rheumatology clinic in Anchorage, where Claribel Tan specialized in treating rheumatoid arthritis, osteoarthritis, and psoriatic arthritis. Her husband did office work and helped manage the clinic.

The two were indicted in July 2024, each charged with one count of healthcare fraud and four counts of willful failure to file a tax return. Daniel Tan is charged with four counts, and Claribel Tan is charged with three counts of attempting to evade taxes. The indictment further stated that “Claribel Tan deceived patients regarding what substances she injected into their bodies” and “both defendants deceived patients regarding the necessity of receiving medication at the clinic.”

Following the indictment, the state medical board suspended Claribel Tan’s medical license in August 2024, stating that she “poses a clear and immediate danger to the public health and safety if she continues to practice.”

“The Tans’ fraud scheme created significant health risks to the patients and caused a loss of approximately $12,522,446 to more than 10 insurance plans,” the US Attorney’s Office stated, adding that the tax fraud scheme caused a loss of $4,249,509 to the Internal Revenue Service. The Tans willfully failed to file tax returns for the clinic from 2018 to 2021, the November 18 press release stated.

According to court documents, Claribel Tan administered and fraudulently billed insurance for medications the Tans did not purchase. Starting in 2009, she routinely underdosed patients, injected them with free samples or a medication different from the one prescribed, injected them with expired medication, and/or injected them with other patients’ medications. Then they billed the payers as though Claribel Tan had properly administered the medication.

“Specifically, the Tans claimed to have administered 4829 units of the medications to patients and billed the insurance plans for that amount, despite only purchasing 369 units of medication,” the press release stated. The Tans also made false statements about the length of Claribel Tan’s office visits and fraudulently billed insurance for services never provided.

The couple will be sentenced on a later date, and each faces a maximum penalty of 10 years in prison for healthcare fraud and 5 years in prison for tax fraud, according to the US Attorney’s Office.

The US Attorney’s Office reported that in 2024 and 2025, it seized $10,471,106 in healthcare fraud proceeds from the Tans. “As part of their plea agreements, the Tans agreed to forfeit those funds to the US and agreed to pay an additional $6,300,849 towards their expected restitution judgment. The Tans further agreed to pay the US an additional $1,855,144 to settle civil claims under the False Claims Act arising from the health care fraud scheme,” the press release stated.