In a week marked by a slowdown in large funding rounds, only three startups secured nine-figure investments. The trend indicates a shift in the investment landscape, with even rounds below $60 million making the list of significant funding announcements.
Helion Energy Secures $425 Million
Helion Energy, a fusion energy startup, raised $425 million in its Series F funding round, bringing its valuation to $5.4 billion. This funding will aid the company’s efforts to commercialize its fusion technology. Investors in this round included notable names such as Lightspeed Venture Partners and SoftBank Vision Fund 2. With this latest round, Helion has raised over $1 billion to date. The company has also entered into agreements with Microsoft to supply electricity from its fusion plant starting in 2028 and with Nucor for a future power plant. Helion’s seventh-generation prototype, Polaris, is expected to demonstrate the first electricity generated from fusion.
Key takeaways
- Only three startups raised nine-figure rounds, a slow enough week that rounds under $60 million made the list.
- Helion Energy raised $425 million in a Series F at a $5.4 billion valuation, taking its total past $1 billion.
- Helion has agreed to supply Microsoft with electricity from a fusion plant starting in 2028 and has a further plant agreement with Nucor; its Polaris prototype is intended to demonstrate the first electricity generated from fusion.
- Voice AI company ElevenLabs raised $180 million led by Iconiq Growth and Andreessen Horowitz at a $3.3 billion valuation.
- Defence again featured, with Castelion raising $100 million in debt and equity to mass-produce affordable hypersonic strike weapons.
ElevenLabs Raises $180 Million
Voice AI startup ElevenLabs secured $180 million in funding, led by Iconiq Growth and Andreessen Horowitz, achieving a valuation of $3.3 billion. This funding follows an earlier $80 million Series B round. ElevenLabs specializes in AI software that allows users to replicate voices in multiple languages, catering to creators and enterprises alike. Since its inception in 2022, the company has raised a total of $281 million.
Openly Raises $123 Million
Openly, an insurtech startup based in Boston, raised $123 million in equity financing, led by Eden Global Partners. The company provides independent insurance agents with a platform that enhances coverage options for homeowners. Openly has raised nearly $431 million since its founding in 2017, including a $100 million Series D earlier this year.
Atalanta Therapeutics Completes $97 Million Round
Atalanta Therapeutics, a Boston-based biotech firm focused on RNA interference therapies for neurological diseases, completed a $97 million Series B funding round. Co-led by EQT Life Sciences and Sanofi Ventures, this funding will support clinical trials for its experimental therapies targeting conditions like KCNT1-related epilepsy and Huntington’s disease. To date, Atalanta has raised $207 million since its founding in 2018.
Mercor and Veir Each Raise $75 Million
Both Mercor, a recruiting startup, and Veir, a developer of superconducting platforms for AI-driven data centers, raised $75 million in their respective funding rounds. Mercor’s valuation reached $2 billion, while Veir has raised nearly $112 million since its founding in 2019.
Castelion Secures $70 Million
Castelion, a defense manufacturer specializing in hypersonic strike weapons, raised $100 million in a mix of debt and equity. This funding will support the development of affordable, mass-produced hypersonic weapons. The company is part of a growing trend in defense tech, which has seen significant funding in recent months.
Helicore Biopharma and Smart Wires Each Raise $65 Million
Helicore Biopharma, focused on obesity treatment, and Smart Wires, which develops solutions for a reliable power grid, both raised $65 million in their funding rounds. Helicore emerged from stealth mode with its Series A funding, while Smart Wires has raised a total of $248 million since its founding in 2010.
Rad AI Raises $60 Million
Rad AI, an AI-enhanced radiology firm based in San Francisco, secured $60 million in funding, led by Transformation Capital. The company has raised over $140 million since its establishment in 2018.
Global Funding Highlights
Outside the U.S., Spain-based TravelPerk, a platform for managing business travel, raised $200 million in its Series E funding round, achieving a valuation of $2.7 billion.
Funding Methodology
This report tracks the largest announced funding rounds for U.S.-based companies over a seven-day period. While most rounds are captured in the database, there may be slight delays in reporting.
Frequently asked questions
Why is Helion's Microsoft agreement significant?
It is a commercial power purchase commitment with a date attached — electricity from 2028 — rather than a research partnership. That moves fusion from laboratory milestone toward contracted supply, assuming the technology delivers.
What does ElevenLabs sell?
AI software that replicates voices across multiple languages, aimed at both individual creators and enterprises. It had raised $281 million in total since being founded in 2022.
What was the largest round outside the US?
Spain-based TravelPerk, which manages business travel, raised $200 million in a Series E at a $2.7 billion valuation.
