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Who invested in Castelion’s Series B?
Castelion named Altimeter Capital and Lightspeed Venture Partners as the round’s leads. It also listed participation from Lavrock Ventures, Andreessen Horowitz, General Catalyst, First In, Space VC, Cantos, BlueYard, Avenir, Champion Hill, and Interlagos, according to the company’s December 5, 2025 announcement.
The $350 million is the amount Castelion said it had closed, not an amount it was still seeking at the time of that announcement.
What did the $350 million Series B fund?
Castelion said it would use the financing to advance several parts of its business. These were company-stated priorities, not confirmation that the work was completed.
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- Integrating Blackbeard: The company planned to integrate the missile with U.S. Army and Navy platforms.
- Building Project Ranger: The funding was intended to support a solid rocket motor manufacturing and final-assembly campus in Sandoval County, New Mexico.
- Testing across services: Castelion said it planned multi-service platform tests in 2026.
- Developing another product line: The company said it would mature a second hypersonic product line.
Castelion CEO and co-founder Bryon Hargis described the intended pace and scale in the announcement: “This funding lets us build fast, test often, and produce at volumes that matter in the real world.”
What are Blackbeard and Project Ranger?
Blackbeard
Blackbeard is the hypersonic missile program Castelion aimed to integrate with Army and Navy platforms. The company said it conducted more than 20 development flight tests in 2025 and described internally developed components including solid rocket motors, control actuation systems, flight computers, seekers, thermal protection materials, and mission software. Those are Castelion’s reports; the available government documentation does not independently establish the missile’s performance or operational readiness.
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Project Ranger
Castelion described Project Ranger as a 1,000-acre campus in Sandoval County for solid rocket motor manufacturing and final assembly. The company said the site was intended to be capable of producing thousands of Blackbeard missiles annually. That figure describes planned capacity, not demonstrated output.
How does the Series C change the picture?
On August 19, 2026, Castelion announced a $1 billion Series C to scale Blackbeard production and expand its portfolio to longer-range strike weapons and defensive systems, according to its Series C announcement. The Series B therefore should be understood as an earlier financing milestone, rather than the company’s latest announced round.
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What has Castelion said about Navy orders?
Castelion’s Project Ranger timeline lists a $23.4 million Navy order in June 2026 and a September 2026 Navy production delivery order valued at up to $200 million for an initial lot of Blackbeard weapons. These amounts and descriptions are presented on the company’s timeline; they should not be treated as independently verified contract totals without government award documentation clarifying the scope of each order.
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