Proterra has authorized shares to raise $75 million, a new round of funding that would push the electric bus maker’s valuation past $1 billion, TechCrunch has learned.

The company authorized the sale of 10,857,762 shares at a price of $6.91 in a Series 8 round, according to a securities filing that was obtained by the Prime Unicorn Index, a company that tracks the performance of private U.S. companies, and reviewed by TechCrunch. If all of the shares are issued, the company’s total valuation would be $1.04 billion, pushing it into “unicorn” territory, according to Prime Unicorn Index.

Proterra declined to comment.

Efforts to raise capital come as the company explores an IPO, according to a report last month by Reuters that said Proterra had hired underwriters from Deutsche Bank, JPMorgan Chase and Morgan Stanley.

Prior to this August 2 filing, Proterra had raised a total of $551.77 million in funding from investors that include G2VP, Kleiner Perkins Caufield & Byers, Constellation Ventures, Mitsui & Co. as well as BMW i Ventures, Edison Energy, the Federal Transportation Administration, General Motors’s venture arm and Tao Capital Partners.

Proterra produces electric buses for municipal, federal and commercial transit agencies; it has a line of electric buses, hundreds of which have been sold, that can travel 350 miles on a single charge. The Burlingame, Calif. company, which has a number of former Tesla employees in leadership positions, including CEO Ryan Popple, has since diversified its business.

Proterra rolled out in April a $200 million credit facility backed by Japanese investment giant Mitsui & Co. to scale up a battery leasing program aimed at lowering the barrier of entry of buying an electric bus.

And just this month, the company announced it has added a new business line called Proterra Powered that will sell its vehicle battery systems, powertrain technology and charging infrastructure to commercial truck and manufacturers of heavy-duty vehicles like garbage trucks.

This new business line stems from its previous relationships with companies like Van Hool and Daimler. Proterra announced last year it was working with Daimler to electrify the company’s Thomas Built Buses division, which makes a line of school buses. That relationship comes with some financial backing and an agreement to share technologies.

Daimler co-led a $155 million funding along with Tao Capital Partner. Proterra is lending its battery and drive train expertise; Daimler will show Proterra how to scale its manufacturing business even further.

The partnership has already been fruitful. Thomas Built Buses received certifications from the California Air Resources Board and the Hybrid and Zero-Emission Truck and Bus Voucher Incentive Project for an electric bus, known as the Saf-T-Liner C2 Jouley, which uses Proterra technology. Electric school bus production for demonstration and innovation vehicles begins in 2019 and commercial production begins in 2020.