Castelion Raises $350 Million in Series B Round
Castelion, an El Segundo, CA-based startup specializing in hypersonic missile development, announced the successful closure of its $350 million Series B funding round on Friday, December 5th. This round was led by Altimeter Capital and Lightspeed Venture Partners, with Lavrock Ventures, Andreessen Horowitz, General Catalyst, First In, Space VC, Cantos, BlueYard, Avenir, Champion Hill, and Interlagos participating. The funding round, first reported in July, brings Castelion’s total funding to $464 million with a valuation of approximately $2.8 billion.
Castelion, founded in late 2022 by former SpaceX employees, CEO Bryon Hargis, COO Sean Pitt, and CFO Andrew Kreitz, became a notable name in defense, focusing on hypersonic missile production after identifying a gap in U.S. capabilities. The necessity for a dependable manufacturer of hypersonic missiles was underscored when a Navy officer contacted Hargis, highlighting the urgent challenges confronting his department.
According to Hargis, “This funding enables us to accelerate development, increase testing frequency, and scale production to meet real-world requirements.” The company’s flagship hypersonic missile, Blackbeard, “helps close America’s hypersonic capability gap against China and Russia.”
The Blackbeard missile is positioned as a cost-effective alternative to systems such as Lockheed Martin’s “Dark Eagle” Long Range Hypersonic Weapon (LRHW), which reportedly costs approximately $41 million. According to company representatives, Blackbeard is expected to be priced in the “hundreds of thousands of dollars.”
Castelion’s unique approach of manufacturing multiple components internally has transformed how hypersonic missiles are made. Unlike traditional contractors who typically purchase parts from different sources, often causing delays, Castelion’s approach streamlines production. By working with unconventional suppliers, the company is able to cut both costs and turnaround times significantly.
Castelion has experienced rapid growth in spite of initial challenges, such as being rejected by over 50 investors before Lavrock Ventures invested an initial $2 million in April 2023. In May 2023, Castelion was awarded its first government contract, valued at $5 million, and completed a $14 million seed round, followed by a $100 million Series A in January 2024. In October, Castelion announced multiple awards for integrating Blackbeard onto operational platforms within the US Army and Navy. Additionally, the missile received a $25 million allocation in the Army’s budget request for development of a variant compatible with HIMARS launchers. To date, Castelion has garnered over $100 million in military contracts.
Castelion also revealed plans in November to construct a hypersonic production and testing facility in New Mexico, with construction slated to begin in January. The facility, which is set to open next year, is projected to reach full operational capacity by 2027. A substantial portion of the $350 million raised will be allocated to building and scaling this facility, including a planned investment of $100 million by Castelion under “Project Ranger.” At full capacity, it is anticipated that the facility will produce thousands of Blackbeard missiles annually.
The company intends to expand testing next year, featuring more complex demonstrations and integration with operational launch platforms. Plans are underway for the introduction of a second hypersonic product line, utilizing shared, cost-efficient subsystems. According to Castelion, the company conducted over 20 flight tests in 2025 and aims to significantly increase this number in the following year.
Leading industry investors have expressed support for Castelion’s strategic vision and rapid development pace. Alex Poulin, a Partner at Lavrock Ventures, remarked, “Hypersonics have true significance only if they can be produced at scale. Castelion’s team is delivering a production-ready solution tailored for practical manufacturing and deployment, and we are proud to support their focus on capacity and tangible results.” With the U.S. government’s hypersonic missile budget estimated at $10 billion for the coming year, Castelion is strategically positioned to secure a substantial portion of these funds, though will face competition from established defense contractors.