¸½½üÉÏÃÅ

Want to keep track of the largest startup funding deals in 2025 with our curated list of $100 million-plus venture deals to U.S.-based companies? Check out The ¸½½üÉÏÃÅ Megadeals Board.

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.

Another week and another big artificial intelligence round. All in all it was an active week with a half-dozen rounds of $100 million or more, with everything from AI to blockchain to biotech getting serious cash.

1. , $2B, artificial intelligence: AI research lab Safe Superintelligence snatched its second big raise in fewer than seven months. SSI, co-founded by ‘s former chief scientist , raised a $2 billion round at a $32 billion valuation led by . The startup, which is looking to develop safe artificial intelligence systems, raised a $1 billion round from a litany of big-name investors including and last September.

2. , $258M, energy: Mainspring Energy secured a $258 million Series F led by . The Menlo Park, California-based firm builds generators — a business that has become appealing to investors as artificial intelligence continues to suck down energy. The company already is shipping generators — which can provide 10s of megawatts of power — to U.S. data center customers this year. Founded in 2010, the company has raised $813 million,

3. , $153M, blockchain: Web3 funding has been on the rise, and this week saw a good-sized round. Santa Clara, California-based Auradine, a developer of sustainable Bitcoin mining and AI data center networking solutions, raised a $153 million Series C led by . Founded in 2022, Auradine has raised more than $300 million, per the company.

4. , $115M, biotech: San Carlos, California-based Glycomine, a biotech startup  developing new therapies for orphan diseases, announced a $115 million Series C led by funds managed by , and . The company plans to use the new cash to advance its lead candidate into a phase 2b clinical trial. Founded in 2013, the company has raised $195 million, .

5. , $104M, biotech: A competitor raised big this week with a $104 million round led by . The Alameda, California-based biotech — which was founded by a Neurolink co-founder, is working on both a brain implant system and a retina implant to treat eye diseases. Founded in 2021, the company has raised $177 million, .

6. , $100M, data: San Mateo, California-based Hammerspace, a data platform for AI, raised a $100 million round led by . Founded in 2018, the company has raised nearly $157 million, .

7. , $90M, biotech: San Carlos, California-based Attovia Therapeutics, which is developing biotherapeutics focused on immune-mediated diseases, closed a $90 million Series C led by . Founded in 2023, Attovia has raised $255 million, .

8. (tied) , $75M, healthcare: New York-based Chapter, a Medicare navigation platform which helps seniors find coverage, raised a $75 million Series D led by . Founded in 2020, the company has raised $184 million, .

8. (tied) , $75M, cybersecurity: Exaforce locked up a $75 million Series A funding led by , 1Ìý²¹²Ô»å . The San Jose, California-based startup is helping bring artificial intelligence agents to security operations centers. The idea is, with the help of data, to significantly reduce human-led SOC work while improving security outcomes.

10. , $63M, fintech: Cincinnati-based Luma Financial Technologies, a fintech for banks and brokers, closed a $63 million Series C led by . Founded in 2018, the company has raised $93 million, .

Big global deals

The biggest raise this week outside the U.S. came from China.

• Beijing-based , an AI-driven startup in the autonomous driving sector, raised a $200 million Series B.

Methodology

We tracked the largest announced rounds in the ¸½½üÉÏÃÅ database that were raised by U.S.-based companies for the seven-day period of April 12 to April 18. 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: