Sequoia Capital early partner Stephanie Zhan stated that there is a saying within Sequoia: some founders are like mules, while others are holding onto a thoroughbred. She categorizes Mach Industries founder Ethan Thornton as the latter, noting that she invested in him at 19, and he is now only 22, with an exciting trajectory.

Thornton dropped out of MIT to found Mach, positioning it as a "post-autonomous defense company." Sequoia participated in the seed round in 2023, marking its first check in defense technology, with Stephanie Zhan and Shaun Maguire involved. Bedrock subsequently led a $79 million Series A round, valuing the company at over $300 million. The public financing trajectory accelerated thereafter: a $100 million Series B round in June 2025, valuing it at approximately $470 million; a $300 million Series C round in June 2026, valuing it at $1.8 billion; and three days later, a $600 million Series C extension, with a valuation soaring to $3.7 billion. Investors in the two Series C rounds included Ribbit Capital, Infinite Capital, Bedrock, and Sequoia. Cumulative public financing is approximately in the hundreds of millions. The company also acquired solid rocket motor manufacturer Exquadrum for about $50 million and claimed to have secured contracts with the U.S. Army and other military branches.

Zhan joined Sequoia's early team in 2015, with a bachelor's degree in computer science from Stanford, and claims that most board seats are filled by her as the "first believer" on the day the company was founded, including Linear, Reflection AI, Skild AI, and Ricursive Intelligence. She focuses on artificial intelligence and dynamic founders. Mach is headquartered in Huntington Beach, California, with a public narrative of expanding unmanned systems and propulsion capacity to serve U.S. military and allied customers.

In 2024, there was an English investigative report on its early vision of hydrogen energy replacing traditional propellants, which faced technical, safety, and management controversies; however, the company's financing and valuation continued to be revised upward, with capital continuing to increase manufacturing and platform delivery.

In market mechanisms, this is a premium for defense technology, not a trade in consumer internet traffic. Buyers view young founders as scarce war industrial capacity for venture capital; sellers are teams that can articulate the "post-autonomous" narrative and secure military contracts. Beneficiaries include Sequoia, Bedrock, and Ribbit; those under pressure are traditional contractors expanding production at a conventional pace. Funding has rolled from seed checks to a nearly $4 billion valuation in three years, with the premium coming from military procurement windows and the multiples Silicon Valley is willing to offer a 22-year-old CEO.

Additional structure: Zhan has also invested in 19-year-old founder Evervault. This round's narrative emphasizes vertical integration and flexible manufacturing networks, rather than single-point laboratory prototypes.

Source: Public information