Based on SpaceX's updated IPO prospectus, Elon Musk owns shares in the company worth over $866 billion.

He is already the richest man in the world, but when SpaceX finally makes its hotly anticipated stock market debut, Elon Musk could become the planet's first trillionaire.…

He is already the richest man in the world, but when SpaceX finally makes its hotly anticipated stock market debut, Elon Musk could become the planet's first trillionaire.