NeuralStackAI dominated the latest list of major U.S. startup financings, with Instinct claiming the top spot through a $1 billion Series C round. The San Francisco-based company is developing a personal AI assistant for everyday tasks, and the financing set its valuation at $10 billion. Sequoia Capital, Benchmark and Coatue backed the round.
EliseAI ranked second after raising $350 million at a $4 billion valuation. The New York-based startup uses AI in the home rental industry and is expanding into healthcare, with Andreessen Horowitz and Bessemer Venture Partners leading the financing.
Cybersecurity was another prominent AI investment area. Palo Alto-based Armadin raised $255.5 million in Series B funding for its autonomous-security platform, a round led by Andreessen Horowitz and Accel that valued the year-old company at more than $2.5 billion.
The funding also extended beyond software applications into the infrastructure supporting AI development. GMI Cloud raised $223 million in Series B funding and secured an additional $445 million in debt financing for its GPU cloud infrastructure, with Archiv leading the round and Nvidia participating. CScale separately emerged from stealth with $145 million in Series C funding for optical interconnect technology aimed at AI data centers.
Several other companies represented different parts of the emerging AI stack. General Intuition secured $220 million to develop models trained on videos and virtual worlds to build skills for physical environments, while SiMa.ai raised $150 million for a software platform designed to scale physical AI applications. Supabase also announced $150 million for its AI-enabled open source Postgres platform for app developers and said it was acquiring database architecture startup Turso.
Not every large deal was AI-focused. Kahua raised $250 million in growth funding from Bain Capital Tech Opportunities for its enterprise platform for managing complex capital projects, reaching a valuation of more than $1 billion. Homeward, which helps homeowners buy before selling or receive cash offers, raised $120 million in Series D equity funding and secured $330 million in debt financing.
Why this matters
The week’s funding pattern suggests that investor appetite is spreading across the full AI ecosystem rather than concentrating only on model developers. Capital went to assistants, housing software, cybersecurity, GPU cloud services, physical AI and data-center connectivity, while adjacent developer infrastructure also attracted a major round. That breadth indicates that investors are backing both visible AI applications and the underlying systems required to operate them.
The deals also show how quickly large private valuations are being assigned to young companies. Instinct reached a $10 billion valuation a year after its founding, while Armadin surpassed $2.5 billion after another year in operation and General Intuition reached $6.2 billion. The figures reflect the scale of expectations surrounding startups positioned around AI’s next commercial and physical applications.
Crunchbase compiled the ranking from announced funding rounds raised by U.S.-based companies between Sept. 26 and Oct. 2, 2026. The database may contain a small reporting delay because some rounds are announced late in the week, so the list reflects the largest deals recorded for that period rather than every financing necessarily announced during it.