UnitedHealth Group (UNH) chief executive Andrew Witty was asked to share detailed information on the company's Medicare billing practices by Sen. Chuck Grassley, R-Iowa, The Wall Street Journal reported Tuesday.

In a letter to Witty, Grassley, chairman of the Senate Judiciary Committee, asked the company to hand over training manuals and guidance documents that allegedly led to extra payments to the company.

On Friday, the Wall Street Journal reported the company was under scrutiny by the US Department of Justice for allegedly encouraging doctors to record diagnoses that result in extra payments to the insurer's Medicare Advantage plans.

The company rejected the claims.

Grassley reportedly cited findings from a series of Wall Street Journal articles published over the last year in asking for further information from the company, WSJ said.

UnitedHealth did not immediately respond to a request for comment from MT Newswires.

(Market Chatter news is derived from conversations with market professionals globally. This information is believed to be from reliable sources but may include rumor and speculation. Accuracy is not guaranteed.)

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