Largest Financings Went To Defense, Wearables, Energy And Security

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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 last week’s hugegest funding deal roundup here.

Startup investors kept up the busy dealcreating pace this week with a number of huge rounds. Top among them was a $1.75 billion Series D for Saronic, developer of autonomous vessels. Other huge funding recipients hailed from sectors including fitness wearables, energy tech, cybersecurity and AI infrastructure, among others.

1. Saronic, $1.75B, autonomous ships: Austin-based Saronic, a defense tech startup focutilized on autonomous sea vessels, raised $1.75 billion in Series D funding, bringing total funding to around $2.6 billion. Kleiner Perkins led the round, which set a $9.25 billion valuation for the company, more than double its Series C level in 2025.

2. Whoop, $575M, fitness wearables: Whoop, a provider of wearable fitness technology and a subscription platform that tracks physiological data, secured $575 million in Series G funding. Collaborative Fund led the financing,which set a $10.1 billion valuation for the Boston-based company.

3. Valar Atomics, $450M, nuclear energy: El Segundo, California-based nuclear energy startup Valar Atomics, raised fresh capital at a valuation of $2 billion, according to a Bloomberg article citing unnamed sources. The financing reportedly included $340 million in equity funding and $110 million in debt.

4. EnerVenue, $300M, battery technology: EnerVenue, a developer of grid-scale energy storage technology, declares it closed on a $300 million extension of its Series B preferred round led by Full Vision Capital. The Fremont, California-based company also appointed a new chief executive officer, Henning Rath.

5. Tenex.AI, $250M, cybersecurity: Sarasota, Florida-based AI-enabled cybersecurity startup Tenex picked up $250 million in Series B funding led by Crosspoint Capital Partners. The company stated it plans to utilize the funds to hire more than 250 people and supplying them with AI technology that creates them “ten times more efficient.”

6. Also, $200M, micromobility: Also, an electric mobility company spun out of Rivian, raised $200 million in a Series C round backed by Greenoaks, DoorDash, and Prysm Capital. The Palo Alto, California-based startup’s product lineup includes bikes, tiny autonomous EVs for deliveries, and associated gear.

7. Starcloud, $170M, space tech: Starcloud, a space infrastructure startup focutilized on building orbital data centers, secured $170 million in Series A funding led by Benchmark and EQT. The financing sets a $1.1 billion valuation for the Redmond, Washington-based company, creating it the rapidest Y Combinator alum to achieve unicorn status after demo day, which was 17 months ago.

8. ScaleOps, $130M, cloud infrastructure: New York-based cloud and AI infrastructure startup ScaleOps landed $130 million in Series C funding. Insight Partners led the financing, which set a valuation of over $800 million for the 4-year-old company.

9. Ambrosia Biosciences, $100M, biotech: Boulder, Colorado-based Ambrosia Biosciences, a developer of next-generation oral therapeutics for obesity and related cardiometabolic diseases, picked up $100 million in Series B funding led by Blue Owl, Redmile Group and Deep Track Capital.

10. OpenFX, $94M, money transfer: OpenFX, provider of a platform to shift money across borders, secured $94 million in Series A funding from backers including Accel, Atomico, M13, Northzone and Pantera Capital.

Methodology

We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the period of March 28-April 3. Although most announced rounds are represented in the database, there could be a tiny time lag as some rounds are reported late in the week.

Illustration: Dom Guzman