5 December 2025 of the year defense technology startup Castelion, led by former SpaceX engineers, announced the engagement $350 million in the Series B funding round. The funds will be used to accelerate mass production of hypersonic weapons for the Pentagon.
The startup positions itself as a vertically integrated manufacturer of hypersonic missiles - the industry, in which US officials admit lagging behind China and Russia. Castelion's first weapon is being developed for the US Army and Navy, in addition, the company received several research and development contracts from the US Air Force Laboratory (Affl). Last month, the company unveiled plans for a campus with an area of approx 405 ha near New Mexico, dedicated to hypersonic systems of the new generation. Production of solid rocket engines is planned at the site, static tests and final assembly of finished ammunition.
The investment reflects growing investor interest in defense startups, hardware-oriented, which promise rapid development cycles and commercial production methods. The main attraction of Castelion is its speed. The company was founded by a special team of SpaceX representatives, which is just for 2,5 years passed the path from a clean sheet to over 25 hypersonic missile flight tests and major integration contracts".
The Series B round was a continuation of the stable growth of funding. In January 2025 year Castelion attracted $100 millions, of which $70 million - Series A round led by Lightspeed and $30 million - venture debt from Silicon Valley Bank. Before that, there was a seed round on $14,2 A million.
Source: https://spacenews.com