Oct 29, 2025

Key Insights – September 2025 September 2025 marked an extraordinary month for US venture capital with $30.91B invested across 533 companies, showing a 281.6% increase from August 2025’s $8.19B and a remarkable 311.9% year-over-year increase from September 2024’s $7.5B. The monthly total was dominated by Anthropic’s record-breaking $13B Series F round, alongside continued massive investments in AI infrastructure, quantum computing, and robotics. Artificial Intelligence dominated funding with an estimated $23.2B across AI-related companies (75% of total funding). 🚀 REACH NYC TECH LEADERS AlleyWatch is NYC’s leading source of tech and startup news, reaching the city’s most active founders, investors, and tech leaders. Advertise today → Total Funding 💡 CONNECT WITH NYC INNOVATORS AlleyWatch is NYC’s leading source of tech and startup news, reaching the city’s most active founders, investors, and tech leaders. Learn more → Detailed Analysis Market Context Total US startup funding in September 2025 reached $30.91B across 533 companies, representing a remarkable 281.6% increase from August 2025’s $8.19B and an extraordinary 311.9% surge compared to September 2024’s $7.5B. This historic month was anchored by Anthropic’s record-breaking $13B Series F round, which alone accounted for 42% of the month’s total funding. Key Metrics Median deal size: $7.0M (showing healthy mid-market activity) Largest deal: Anthropic at $13.0B Funded companies: 533 (35.6% increase from August) AI funding share: 75.1% of total funding ($23.22B) Series B + Late-stage concentration: 86.9% of total funding Industry Insights Artificial Intelligence Infrastructure dominated the funding landscape with Anthropic’s $13B Series F leading a wave of massive AI investments. Cerebras Systems ($1.1B for AI chips), Databricks ($1.0B for data/AI platform), and Groq ($750M for inference chips) highlighted the infrastructure arms race supporting the AI boom. Deep Technology Breakthroughs attracted significant capital with PsiQuantum securing $1.0B for quantum computing, Figure raising $1.0B for humanoid robotics, and Cognition landing $400M for AI development tools. These investments signal strong investor confidence in transformative hardware and fundamental technology advances. Geographic Concentration intensified with San Francisco capturing 100 deals (18.8% of total) and New York securing 79 deals (14.8%), together accounting for over one-third of all transactions. The Bay Area’s dominance in mega-rounds likely captured over 60% of total funding value. Notable Trends Stage Divergence: Late-stage deals averaged $452.2M while Early-stage averaged just $6.3M—a 72x difference AI Dominance: 224 AI-related companies secured funding, representing 42% of all deals but 75% of capital Sustained Early-Stage Activity: Despite mega-round dominance, 298 Early-stage deals showed healthy ecosystem fundamentals Developer Platform Growth: Vercel ($300M), Sierra ($350M), and Kraken ($500M) highlighted continued platform investments Join thousands of NYC tech leaders who start their day with AlleyWatch