Theranos Inc.’s 15-year odyssey to revolutionize the blood-testing business began with huge promise but has been engulfed by ignominy.

Company founder Elizabeth Holmes, widely hailed as Silicon Valley’s first female billionaire startup founder, agreed to a settlement with federal regulators that strips her of voting control of Theranos, bans her from being an officer or director of any public company for 10 years and requires her to pay a $500,000 penalty.

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