"She refused to stop overpromising to investors," said Pulitzer Prize-winning Wall Street Journal reporter John Carreyrou. He says he isn't surprised that Theranos founder Elizabeth Holmes is facing federal fraud charges.
VIDEO: Journalist who broke Theranos fraud story walks through investigation
"It's a fraud that not only defrauded investors but put patients in harm's way," he added.
Carreyrou's new book, "Bad Blood: Secrets and Lies in a Silicon Valley Startup" details the rise and fall of the blood testing company. He said that he was threatened with lawsuits while doing his research. Holmes allegedly asked Wall Street Journal owner and Theranos investor Rupert Merdoch to intervene.
"She had met with him and tried to persuade him to kill the story," said Carreyrou.
Stanford University Medical School Professor Phyllis Gardner was an early critic of Holmes and her blood testing idea. "I tried to tell her the idea wouldn't work. She wouldn't listen. For me, a vindication, I was right," she said.
"Unfortunately it was too good to be true," said Professor Christine Rosen of the Haas School of Business. She had high hopes for Holmes and Theranos. "She, as a cutting edge pioneering woman in this area -- it was a big fizzle."
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