AI-driven companies anchored the week’s largest U.S. startup financings, led by Tenstorrent’s $1.5 billion Series E and Flapping Airplanes’ $1 billion Series A, based on announced rounds from Oct. 17–23, 2026.
AI-driven rounds top the list
1. Tenstorrent — $1.5B, AI infrastructure: Santa Clara, California-based Tenstorrent, a developer of AI processors and systems, secured $1.5 billion in Series E funding. The round was led by Trace Capital and Innovation X and set a $6.2 billion valuation for the 10-year-old company.
2. Flapping Airplanes — $1B, foundational AI: Flapping Airplanes, an AI lab focused on developing models that cost less to train and run, closed a $1 billion Series A led by Lux Capital and Index Ventures. The round follows a $180 million seed financing raised less than 10 months earlier by the year-old San Francisco startup.
3. ASI — $325M, AI for critical infrastructure: ASI, a developer of AI technology for securing and operating critical infrastructure in aviation, transportation and defense, picked up $325 million in Series C financing led by Spark Capital. The round set a $3 billion valuation for the Boston-based company.
4. Xona — $250M, space tech: Xona, a Burlingame, California-based startup developing a next-generation version of GPS, raised $250 million in Series D funding led by Future Ventures. The round sets a $2.4 billion valuation.
5. Pathos AI — $237M, biotech: Pathos AI, a New York-headquartered startup applying AI to drug development, completed a $237 million Series E financing at a post-money valuation around $3 billion. Bristol-Myers Squibb led the financing.
6. Warp Sciences — $215M, AI, robotics and life sciences: Warp Sciences, a startup applying AI and robotics to accelerate medicine development, raised a $215 million Series A led by Lightspeed Venture Partners.
Other notable financings
7. (tied) Whop — $200M, online business marketplace: Whop, a platform that helps entrepreneurs build and run online businesses, secured $200 million in Series D funding led by Sequoia Capital and Shopify Ventures. The round set a $5.1 billion valuation for the New York-based company.
7. (tied) Star Therapeutics — $200M, biotech: South San Francisco-based drug developer Star Therapeutics said it raised $200 million in new financing led by OrbiMed and Janus Henderson Investors. The investment follows Incyte’s July acquisition of Vega Therapeutics, a subsidiary of Star, in a deal valued at up to $2 billion.
7. (tied) Warhound — $200M, military dogs: Warhound, a startup that wants to breed working dogs for U.S. military forces and emergency responders, launched from stealth with $200 million in seed funding from a long list of backers including Sequoia Capital and 8VC. The startup, co-founded by AnduriI ndustries founder Palmer Luckey, plans to equip the dogs with Anduril technology.
10. Arda Industries — $160M, AI manufacturing software: Arda Industries, a developer of AI-powered software for manufacturing engineering, closed a $160 million Series A at a $1.5 billion valuation, co-led by Altimeter Capital, Accel and Khosla Ventures. The San Francisco-based startup also announced a previously undisclosed $72 million seed financing.
Methodology: The list tracks the largest announced rounds in the Crunchbase database that were raised by U.S.-based companies for the period of Oct. 17–23, 2026. Although most announced rounds are in the database, there may be a small time lag as some rounds are reported late in the week.
