The U.S. Supreme Court won’t be weighing in on Joe Nacchio’s claim that he deserves an $18 million tax refund from money the convicted former Qwest CEO made on illegal stock sales.

The Associated Press reports that the high court declined to hear Nacchio’s appeal of an earlier ruling, denying him the refund.

Nacchio, formerly chief executive of Denver-based Qwest Communications International, was convicted a decade ago of insider trading in connection with his sale of Qwest shares worth $52 million, based on what the trial court ruled was insider information that the stock was likely headed for a tumble.

He served nearly six years in federal prison. He also was ordered to forfeit $44.6 million and was fined $19 million. CenturyLink Inc. later bought Qwest.

Read more at Denver Business Journal.