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- 📝 Castelion raising $350M
📝 Castelion raising $350M
News of the Day
Hypersonic weapons startup Castelion is raising a $350 million Series B at a multi-billion-dollar valuation, with Lightspeed and Altimeter Capital leading the round just months after Castelion’s $100 million Series A. Taking a page from SpaceX’s playbook with rapid iteration and vertical integration, Castelion is aiming to mass-produce lower-cost hypersonic missiles, including its Blackbeard Ground Launch system, which is now backed by $25 million in the U.S. Army’s 2026 budget. If initial tests are successful, Castelion could begin delivering missiles in 2028, putting significant pressure on legacy defence giants like Lockheed, Raytheon, and Northrop.
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How to hire great GPs by @bhorowitz (2011):
1. Built something successful
2. Picks great products
3. The best founders want to work with them— a16z (@a16z)
4:00 PM • Jul 4, 2025
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