The Week’s 10 Biggest Funding Rounds: AI, Autonomy And Biotech Top The Ranks

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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 deal roundup here.

This week, just half of the top 10 rounds crossed the $100 million mark, which is somewhat unusual in this high-flying era for venture megarounds. Nonetheless some large checks did get written, led by Amazon’s $5 billion investment and partnership deal with Anthropic. Other sizable rounds went to companies in sectors including aviation autonomy, vision therapy and AI analytics.

1. Anthropic, $5B, foundational AI: AI giant Anthropic announced that Amazon is investing $5 billion in the company, with up to an additional $20 billion in the future. Previously, Amazon had invested $8 billion in the San Francisco-based company. The latest financing also includes a partnership with Amazon for training and deploying Anthropic’s AI assistant Claude.

2. Reliable Robotics, $160M, autonomous aircraft: Reliable Robotics, a developer of autonomous aircraft systems, raised $160 million in fresh financing led by Nimble Partners. The 9-year-old, Mountain View, California-based company markets its technology for both commercial and defense aviation.

3. Ray Therapeutics, $125M, vision therapy: San Diego-based Ray Therapeutics, a biotech startup focused on vision restoration therapies, secured $125 million in Series B funding led by Janus Henderson Investors. Founded in 2021, Ray has raised $247 million in venture and grant funding to date, per Crunchbase data.

4. Omni, $120M, AI analytics: Omni, developer of an AI-enabled analytics platform, closed on $120 million in Series C funding led by Iconiq Growth. The financing set a $1.5 billion valuation for the 4-year-old, San Francisco-based company.

5. Tortugas Neuroscience, $106M, biotech: Framingham, Massachusetts-based Tortugas Neurosciences, neurology-focused biotech startup, scooped up $106 million in Series A funding. Founding investor Cure Ventures co-led the round alongside The Column Group and AN Venture Partners.

6. AcuityMD, $80M, medtech: AcuityMD, an AI-enabled data and research platform for medtech industry customers, picked up $80 million in Series C investment. StepStone Group led the funding for the 7-year-old, Boston-based company.

7. OpenAI, $75M, foundational AI: Robinhood Ventures announced that it purchased $75 million worth of San Francisco-based OpenAI’s common stock. The shares are owned by Robinhood Ventures Fund I, a publicly traded fund that provides investors exposure to a curated portfolio of private companies.

8. Orkes, $60M, workflow orchestration: Orkes, developer of an AI-enabled software workflow orchestration platform, secured $60 million in Series B funding. AVP led the financing for the 5-year-old, Silicon Valley-based startup.

9. Courier Health, $50M, health tech: Courier Health, a developer of tools to improve patient experience for people with chronic conditions or rare diseases, closed on $50 million in Series B funding. Oak HC/FT led the financing for the New York-based company.

10. Serif Biomedicines, $50M, biotech: Cambridge, Massachusetts-based Serif Bio­med­i­cines, a biotech­ startup focused on Mod­i­fied DNA as a new class of med­i­cines, launched with $50 million in initial funding from Flagship Pioneering.

Methodology

We tracked the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the period of April 18-24. 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