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When she was a sophomore at Stanford in 2003, Holmes founded healthcare-technology company Theranos (a few months later, she dropped out to focus on the company). Today, she has a net worth of $4.6 billion.
Theranos is a $9 billion biotech company that has a new approach to blood testing. Its goal is to make clinical testing cheaper and faster.
Theranos wants to conduct blood tests for health issues through a single finger stick rather than by having to draw vials of blood in a doctor's office. Theranos has drawn skepticism from the scientific community in part because Theranos is cagey about how its tests actually work.
But for now, Holmes is on top of the world. Today, her blood tests are used in places like Walgreens.