Jack Dorsey, 40
CEO, Twitter and Square
Twitter’s shares have sunk as the social network struggles to combat hate speech and find a buyer. Including his stake in the payment platform Square, Dorsey has paper losses of $307 million this year through Nov. 21, or 19 percent of his net worth.
Parker Conrad, 36
Former CEO, Zenefits
His company, devoted to disrupting human resources, was caught “disrupting” ethics regulations. Conrad resigned, and Zenefits’ $4.5 billion valuation was cut in half.
Elizabeth Holmes, 32
Her blood-testing company in Palo Alto imploded after it turned out that the tests didn’t work. In July, Holmes was banned from the laboratory business for two years, and her net worth, as estimated by Forbes, was revised from $4.5 billion to $0.
Mike Rothenberg, 32
Founder, Rothenberg Ventures
Notorious among venture capitalists for his lavish parties (they were parodied on the HBO show Silicon Valley), he lost control of his fund this year. Rothenberg Ventures has since been renamed Frontier Tech Ventures. (Robert Lott, an attorney for Rothenberg, said by email: “Mike Rothenberg is still operating the firm as its CEO and is in the office every day.”)
Martin Shkreli, 33
Founder, Retrophin and Turing Pharmaceuticals
The reigning Worst Young Person of 2015—he was the poster child for drug price gouging—is now on trial for securities fraud. He started the year reeling from a $40 million trading loss. Now he’s trying a new, risky defense in court: blaming his lawyers for giving him poor advice.
(Updated to include comment from Rothenberg’s attorney.)