The U.S. Attorney’s Office in Boston has subpoenaed DaVita Inc., Fresenius Medical Care, and the American Kidney Fund (AKF) related to the Health Insurance Premium Program operated by the AKF.

The AKF has denied claims, published in a Dec. 25 article in the the New York Times, that it shows favor in approving applications for premium assistance to those dialysis providers who have paid into the AKF’s Health Insurance Premium Program––a violation of the federal agreement that set up the program over 20 years ago.

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The Times cited comments from social workers at small dialysis clinics who said they were discouraged to apply for the premium assistance fund because their providers had not contributed to the assistance program. That’s contrary to an Office of Inspector General agreement with the AKF and dialysis providers that set up HIPP, requiring that the AKF must offer premium assistance to all qualified patients regardless of whether their provider had paid into the program.

“We never condition our issuing of grants on whether a provider has contributed, and fully 40 percent of dialysis providers with patients receiving help from AKF don’t contribute anything to AKF,” the organization said in response to the article. “We currently have HIPP grant recipients who are treated at more than 200 dialysis companies, spanning the full range of providers from small independent clinics, to mid-sized companies, hospital clinics, and the largest dialysis organizations.”