$1.5B Lambda Deal Leads Massive Week: Top 10 U.S. Startup Mega-Rounds of November 2025 Hit Record $7B+ as AI & Crypto Surge Before Holidays

San Francisco, CA – In one of the busiest weeks ever for U.S. venture mega-deals, startups raised over $7 billion across just ten $100M+ rounds, according to the latest Crunchbase Megadeals Board. AI infrastructure giant Lambda crushed the leaderboard with a staggering $1.5 billion Series E, while predictions platform Kalshi shocked markets with a $1 billion raise at an $11 billion valuation. The flood of capital—driven by AI, crypto, robotics, fintech, and biotech—signals investors are racing to deploy dry powder before year-end.

Here are the top 10 largest U.S. startup funding rounds announced this past week (November 2025):

1. Lambda – $1.5 billion (AI cloud infrastructure) The San Francisco-based leader in GPU cloud for AI training closed a mammoth Series E led by TWG Global (Thomas Tull & Mark Walter). Total funding now exceeds $3.2 billion. Lambda’s platform has become mission-critical for frontier AI labs racing to train ever-larger models.
2. Kalshi – $1 billion (predictions market) New York-based Kalshi, the first federally regulated event-contracts exchange, reportedly raised $1 billion led by Sequoia Capital and CapitalG, catapulting its valuation to $11 billion. The round highlights explosive institutional interest in real-money prediction markets.
3. Luma AI – $900 million (multimedia generative AI) The Silicon Valley startup behind Luma Dream Machine and cutting-edge video generation locked in $900 million Series C led by Humain with major participation from AMD, cementing its place as a leader in frontier multimodal AI.
4. Kraken – $800 million (cryptocurrency exchange) One of the oldest U.S. crypto exchanges raised $800 million across primary and strategic tranches, including a $200 million investment from Citadel Securities that values Kraken at $20 billion—its highest valuation ever as crypto winter fears fade.
5. Physical Intelligence – $600 million (robotics AI) Backed by Jeff Bezos, Thrive Capital, Lux, and Index Ventures, this San Francisco startup developing general-purpose AI software for robots raised $600 million at a reported $5.6 billion valuation in a CapitalG-led round.
6. Ramp – $300 million (corporate spend management/fintech) The New York unicorn closed its fourth mega-round of 2025 alone, a $300 million raise led by Lightspeed Venture Partners that pushes its valuation to $32 billion—making Ramp the most valuable private fintech in America.
7. Function Health – $298 million (longevity & preventive care) Austin-based Function Health, which offers 100+ biomarker tests and clinician coaching for lifespan extension, raised a $298 million Series B led by Redpoint at a $2.5 billion valuation—just three years after founding.
8. Genspark – $275 million (agentic AI for knowledge workers) Palo Alto’s Genspark, building autonomous AI agents that research, write, and act, raised $275 million Series B at $1.25 billion valuation while already surpassing $50 million ARR in under six months.
9. Suno – $250 million (AI music generation) The Cambridge, MA-based platform that lets anyone create full songs with AI closed $250 million Series C led by Menlo Ventures at $2.45 billion valuation, fueling the creative AI arms race alongside competitors like Udio.
10. Solve Therapeutics – $120 million (cancer antibody therapeutics) San Diego biotech Solve Therapeutics raised $120 million led by Yosemite to advance its next-generation antibody-drug conjugates targeting solid tumors, rounding out a week that wasn’t just AI and crypto.

Key Takeaways from the Week

• AI dominance continues: 6 of the top 10 deals (Lambda, Luma, Physical Intelligence, Genspark, Suno, and partially Ramp) were AI-centric.
• Crypto roars back: Kraken and Kalshi together raised $1.8 billion as institutional money floods prediction markets and exchanges.
• Valuation explosion: Four companies (Kalshi $11B, Ramp $32B, Kraken $20B, Physical Intelligence $5.6B) now sit among the most valuable private U.S. startups ever.
• Pre-holiday sprint: Investors appear to be closing massive term sheets before Thanksgiving and December slowdowns.

The Crunchbase Megadeals Board, which tracks every disclosed $100 million+ round to U.S.-based companies, has never recorded a denser week of billion-dollar-plus raises. With dry powder at all-time highs and frontier AI models still requiring enormous capital, 2025 is on pace to shatter previous venture records.