The Week’s Biggest Funding Rounds: Helion Energy Takes Top Spot In Another Slow Week

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This is a weekly feature that runs down the week’s top 10 announced funding rounds in the U.S. Check out the biggest funding rounds of last week here.

While the year started out hot for large megaround deals, it has slowed considerably. Just three startups raised nine-figure rounds this week and you barely needed a round of $60 million to make this list.

1. Helion Energy, $425M, energy: Fusion startup Helion Energy locked up a $425 million Series F — valuing the company at $5.4 billion — as the company looks to commercialize its fusion technology. The round included participation from investors including Lightspeed Venture Partners, SoftBank Vision Fund 2 and Sam Altman. The Everett, Washington-based startup has now raised more than $1 billion. In November 2021, Helion closed a $500 million Series E. The new round further illustrates investors’ appetite for new energy sources as power needs increase due to AI and other advances. In 2023, Helion announced a power purchase agreement with Microsoft to deliver electricity from its fusion plant starting in 2028, and a customer agreement with Nucor to develop a power plant in the 2030s. Helion has just started operating its seventh generation prototype, Polaris, which is expected to demonstrate the first electricity produced from fusion. The company’s new round is the second-largest in the fusion sector since the start of last year, per Crunchbase data. Last October, Pacific Fusion, a startup attempting to create a nuclear fusion-based energy source, raised more than $900 million in a Series A led by General Catalyst.

2. ElevenLabs, $180M, artificial intelligence: Voice AI startup ElevenLabs raised a $180 million round led by Iconiq Growth and Andreessen Horowitz at a $3.3 billion valuation. The raise comes about a year after the startup locked up an $80 million Series B at a unicorn valuation. The Brooklyn-based company allows creators, enterprises and others to use AI software to replicate voices in dozens of languages. Founded in 2022, ElevenLabs has raised $281 million, per Crunchbase.

3. Openly, $123M, insurance: The most expensive purchase most people will ever make is their home, so it matters who insures it. Openly provides independent insurance agents with a platform that offers coverage to homeowners and streamlines processes, improves risk underwriting and helps with claims. The Boston-based insurtech startup raised $123 million in equity financing led by Eden Global Partners this week, and another $70 million in debt. In 2023, the company raised a $100 million Series D, also led by Eden Global Partners. Founded in 2017, the company has raised nearly $431 million, per Crunchbase.

4. Atalanta Therapeutics, $97M, biotech: Boston-based Atalanta Therapeutics, a biotechnology using RNA interference for the treatment of neurological diseases, completed a $97 million Series B co-led by EQT Life Sciences and Sanofi Ventures. The company will use the cash to support clinical trials of its experimental RNAi therapies for KCNT1-related epilepsy and Huntington’s disease. Founded in 2018, the company has raised $207 million, per Crunchbase.

5. (tied) Mercor, $75M, human resources: San Francisco-based recruiting startup Mercor raised a $75 million round led by Felicis 1 that values the company at a $2 billion valuation, per a report. The company started the process in December and the final total could still increase. Founded in 2023, the company has raised nearly $109 million, per Crunchbase.

5. (tied) Veir, $75M, power grid: Woburn, Massachusetts-based Veir, a developer of superconducting platforms for AI-driven data centers and utilities, closed a $75 million Series B led by Munich Re Ventures. Founded in 2019, the company has raised nearly $112 million, per Crunchbase.

7. Castelion, $70M, defense: Castelion, a defense manufacturer developing long-range hypersonic strike weapons, raised a $100 million Series A in a mix of debt and equity. The El Segundo, California-based startup creates what it calls “affordable, mass-produced hypersonic long-range strike weapons” that serve as a “non-nuclear deterrent.” The Series A — which includes $30 million in venture debt from Silicon Valley Bank — was led by Lightspeed Venture Partners. Defense tech has garnered major headlines in the past several months after massive raises by the likes of Anduril Industries and artificial intelligence defense software developer Helsing. Just late last year, defense and critical infrastructure tech startup Chaos Industries raised $145 million in a Series B. Already this year, Firehawk Aerospace raised a $60 million Series C and Onebrief locked up a $50 million Series B.

8. (tied) Helicore Biopharma, $65M, biotech: South San Francisco-based Helicore Biopharma, a biopharmaceutical startup focused on the treatment of obesity and related conditions, emerged from stealth mode with $65 million in a Series A co-led by OrbiMed and Versant Ventures.

8. (tied) Smart Wires, $65M, electronics: Durham, North Carolina-based Smart Wires, a company that develops solutions for a more reliable and affordable power grid, raised $65 million in a new investment that included participation from BP Energy Partners. Founded in 2010, the company has raised $248 million, per Crunchbase.

10. Rad AI, $60M, health care: San Francisco-based Rad AI, an artificial intelligence-enhanced radiology firm, reportedly locked up a $60 million round led by Transformation Capital that values the company at $525 million. Founded in 2018, Rad AI has raised more than $140 million, per the company.

Big global deals

The largest deal outside the U.S. came from the Iberian Peninsula.

• Spain-based TravelPerk, an all-in-one platform for managing business travel, raised a $200 million Series E that values the company at $2.7 billion.

Methodology

We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the seven-day period of Jan. 25 to Jan. 31. Although most announced rounds are represented in the database, there could be a small time lag as some rounds are reported late in the week.

Illustration: Dom Guzman