U.S. Education Secretary Betsy DeVos is among a group of high-flying investors who have lost millions of dollars investing in the disgraced Silicon Valley startup Theranos Inc.

The Wall Street Journal first reported the details late Thursday, saying DeVos' family invested $100 million in the blood-testing company, according to previously sealed documents made public this week.

In a government filing, DeVos had earlier said that her family had invested in the company, but the exact amount was undisclosed.

The scandal-plagued Palo Alto, Calif., company is expected to be liquidated later this year, after the U.S. Securities and Exchange Commission said its claims of developing a "groundbreaking" technology that would revolutionize blood testing were false. Its founder, Elizabeth Holmes, settled the charges without admitting wrongdoing, but she also gave back a portion of her company stock, relinquished voting control of the company and paid a $500,000 penalty.

Other investors face large losses as well, The Journal reported, including the heirs of Walmart Inc. founder Sam Walton, who invested $150 million; News Corp executive chairman Rupert Murdoch, who invested $125 million; and Mexican tycoon Carlos Slim, who lost $30 million.

The investors' losses were revealed Thursday in federal court in San Francisco. The documents were unsealed as part of a lawsuit brought against Theranos by Robert Colman, the former Robertson Stephens & Co. co-founder, who has alleged that Theranos made false and misleading claims about its operations and technology. The company denies the charges.

Greg McNeilly, chief operating officer of Windquest Group, the DeVos family holding company, told The Journal that the $100 million investment was made by "many members of the DeVos family,” not just the secretary and her husband. “To say they’re highly disappointed in Theranos as a company and an investment is an understatement,” he said.