The Boring Company has raised $112.5 million in a recent round of funding.
Elon Musk's tunnel-digging company said 90% of the funds raised came from Musk.
The rest came from early employees, and no outside investors were involved.
Musk founded the Boring Company in 2016.
He plans to use the company to create underground tunnel networks for high-speed transportation systems.
In March, Musk said the company's tunnels would prioritize pedestrians and cyclists over cars.
"It's a matter of courtesy & fairness. If someone can't afford a car, they should go first." Elon Musk