U.S. AI Startups Raise Over $100M in 2025, With One Mega-Round Surpassing $1B

• Anthropic raised $3.5 billion in a Series E round on March 3, valuing the company at $61.5 billion.
• ElevenLabs, a synthetic voice startup, secured $180 million in a Series C round on January 30, led by ICONIQ Growth and Andreessen Horowitz.

The AI industry continues its strong funding momentum in 2025, with nine U.S. startups already securing investment rounds of $100 million or more. While 2024 saw 49 such funding rounds, 2025 is shaping up to be another pivotal year, with one company raising over $1 billion in a single round.

March

Anthropic, an AI research and large language model company, secured a massive $3.5 billion in a Series E round on March 3. The round, which valued the startup at $61.5 billion, was led by Lightspeed and included Salesforce Ventures, Menlo Ventures, and General Catalyst.

Anthropic completed a $65 billion Series H in May 2026 at a $965 billion post-money valuation and had filed for a potential 2026 public listing.

February

Together AI, specializing in open-source generative AI and AI model development infrastructure, raised $305 million in a Series B round on February 20. The round, co-led by Prosperity7 and General Catalyst, valued the company at $3.3 billion, with backing from Salesforce Ventures, Nvidia, and Lux Capital.

AI infrastructure firm Lambda raised $480 million in a Series D round on February 19, valuing it at nearly $2.5 billion. The round was co-led by SGW and Andra Capital, with participation from Nvidia, G Squared, and ARK Invest.

Abridge, an AI-powered transcription platform for patient-clinician conversations, raised a $250 million Series D round on February 17, valuing the company at $2.75 billion. The round was co-led by IVP and Elad Gil, with Lightspeed and Redpoint also participating.