For Halloween, Tesla stockholders received a treat. The electric vehicle maker’s stock reached a five-year high of $456.56 a share. Stockholders approved an unprecedented 10-year pay package in November that could be worth $1 trillion for Tesla founder and CEO Elon Musk.

Musk was already the world’s richest man with a personal fortune estimated at almost $500 billion. He has a significant stake in Tesla and private ownership stakes in SpaceX, X, and The Boring Company, among others. This deal has the potential to turn him into the world’s first legitimate trillionaire, even after all taxes are accounted for.