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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 biggest funding rounds here.
The past week brought a varied assortment of large startup financings, with big rounds in sectors ranging from events-based betting to AI to energy to biotech. Leading the pack for round size were prediction market platform Polymarket and open standards-focused AI startup Reflection AI, which each raised $2 billion.
1. (tied) Polymarket, $2B, prediction market: Intercontinental Exchange, the operator of clearing houses and exchanges including the New York Stock Exchange, announced that it will invest up to $2 billion into the prediction market platform Polymarket. The deal sets an $8 billion pre-money valuation for New York-based Polymarket, which lets users wager on event probabilities across markets, politics, sports and other areas.
1. (tied) Reflection AI, $2B, AI: New York’s Reflection AI, a developer of LLM training models based on open standards, raised $2 billion in a funding round backed by Nvidia and a long list of venture investors. The financing sets an $8 billion valuation for Reflection, which is reportedly 15x the valuation it secured just seven months ago.
3. Base Power, $1B, battery power: Base Power, an Austin, Texas-based provider of battery-powered home energy, secured $1 billion in Series C funding led by Addition. Founded in 2023, Base has raised $1.3 billion in known funding to date, per Crunchbase data.
4. Stoke Space, $510M, space tech: Stoke Space, a developer of reusable launch vehicles, picked up $510 million in Series D funding led by US Innovative Technology Fund in conjunction with a $100 million debt facility led by Silicon Valley Bank. The funding will be used toward expanding production capacity in its launch vehicle and activating its launch complex at Cape Canaveral.
5. Expedition Therapeutics, $165M, biotech: San Francisco-based Expedition Therapeutics, a developer of therapies for inflammatory and respiratory diseases, closed on $165 million in Series A funding co-led by Sofinnova Investments and Novo Holdings. Funding will support a Phase 2 study for its drug candidate to treat chronic obstructive pulmonary disease.
6. EvenUp, $150M, legal tech: EvenUp, a legal tech startup that creates artificial intelligence products for the personal injury sector, landed $150 million in Series E funding. Repeat backer Bessemer Venture Partners led the round, which sets a valuation of more than $2 billion for the San Francisco-based startup.
7. Duos, $130M, health benefits: Minneapolis-based Duos, a digital health platform focused on Medicare beneficiaries, locked up $130 million in a growth equity investment led by FTV Capital. Founded in 2020, Duos has raised over $160 million in known funding to date.
8. Nilo Therapeutics, $101M, biotech: Nilo Therapeutics, a startup focused on developing therapies based on advances in neuro-immunology, launched with a $101 million Series A round. The Column Group, DCVC Bio and Lux Capital led the financing for the New York-based company.
9. Torl Biotherapeutics, $96M, biotech: Torl Biotherapeutics, a startup focused on antibody-based immunotherapies for cancer patients, closed on a $96 million Series C round. The Los Angeles company did not disclose investors but did say the funding would go to advance multiple clinical trials in progress.
10. Harvey, $59M, legal tech: Harvey, a provider of AI-enabled tools for legal professionals, raised $59 million from EQT Growth aimed at supporting international expansion. The financing brings total reported funding to date for San Francisco-based Harvey to $865 million, with most of that secured in 2025.
Methodology
We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the period of Oct. 4-10. 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
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