19. JENNY JUST
$1.5 billion SOURCE: Fintech AGE: 53 • RESIDENCE: Winnetka, IL SELF-MADE SCORE: The first-time billionaire started out as an options trader in Chicago, then cofounded options trading firm Peak6 with the man who later became her husband. They have since funneled the profits from trading into more than a dozen businesses. The star investment: Apex Clearing, which handles the back-end trading and technology for fintechs such as SoFi and Ally. It’s slated to go public in a SPAC merger that values the firm at $4.7 billion.