The world’s richest unmarried girl: Elizabeth Holmes

After the end of her freshman year, Holmes worked in a lab at the Genome Institute of Singapore on testing for severe acute respiratory syndrome (SARS) through the collection of blood samples with syringes. She filed her first patent on a wearable drug-delivery patch in 2003. In March 2004, she dropped out of Stanford's School of Engineering and used her tuition money as seed funding for a consumer healthcare technology company