Text-and-Call AI Assistant Instinct’s Valuation Quadruples in a Month, Raises $1B

The category of AI personal assistants you reach by text or phone call — not chatbots that answer, but agents that actually get things done — has suddenly become the hottest battleground in tech, with Big Tech and startups piling in at once.

Instinct said it has raised $1 billion in a Series C round from Sequoia Capital, Benchmark Capital, and Coatue, pushing its valuation to $10 billion. That’s a fourfold jump in a single month since its $250 million Series B at a $2.5 billion valuation this past August.

New features came with the announcement. Instinct Concierge now makes the phone calls a person otherwise would — booking a table at a restaurant that doesn’t take online reservations, or getting on a dentist’s cancellation list. Trusted Person Network lets one person’s assistant talk directly to a friend’s, coordinating plans and trading files like PDFs, images, and spreadsheets. Share your location over iMessage, and it recognizes where you’ve landed and offers suggestions on its own. Security got attention too: the company says it now issues short-lived credentials for each task, runs work in isolated sandboxes, and checks its own answers for subtle hallucinations before sending them.

Founder Noah Shinn, 23, dropped out of Northeastern University in 2023 after studying machine learning and programming languages there and at MIT. He was first author on Reflexion, a 2023 paper proposing that agents summarize their own failures into memory and apply that memory to the next task, and later co-developed the agent-evaluation benchmark τ-bench. He worked as a research scientist at enterprise AI agent company Sierra before leaving in 2025 to found Spear Street Technology, which operates Instinct.

Instinct’s valuation has climbed exponentially in just months. The August Series B was co-led by Index Ventures and Benchmark, with early backers Conviction Partners and Greenoaks. Total funding now stands at roughly $1.35 billion. “We’re building Instinct to be the best personal agent that can handle the deeply personal nuances of everyday life,” Shinn said. “This funding helps us bring Instinct to more people and continue building the future of personal AI.”

Competition is already fierce. Meta’s Muse topped the App Store within two weeks of launch. It matches much of what Instinct does while going deeper into Meta’s own social products — summarizing Instagram DMs, monitoring Facebook Groups, tracking Marketplace listings. Instinct, by contrast, still has no mobile app and communicates purely by text — and has disclosed no user numbers or growth metrics at all.

Shinn’s former employer, Sierra, coincidentally hit the same $10 billion valuation a year ago (it’s since climbed to $15.8 billion) — though in a different market: Sierra charges enterprises per resolved customer-service ticket, while Instinct sells to consumers. In open source, OpenClaw — a free personal AI agent that passed 340,000 GitHub stars in five months — looms as well; its creator, Peter Steinberger, joined OpenAI in February to build next-generation personal agents. Another messaging-based assistant, Poke, was acquired in July by Cognition, maker of the AI coding agent Devin.

The funding frenzy comes with real pushback. A privacy controversy broke out in August, while Instinct was still in private beta. Its original terms of service granted a “perpetual and irrevocable” license to use user materials — including for AI model training — and could capture screen and keyboard input. One user found Instinct still summarizing his inbox three hours after he’d disconnected Google access; the bot admitted the emails were stored in plain text for later search. Startup co-founder Alex Cohen deleted his account after testing how easily Instinct could be phished, and investor Katie Jacobs Stanton wrote that trust “reset to zero” after Instinct sent an email on her behalf without asking first. This round’s security features read as a direct answer to that episode.

There’s skepticism about the round itself, too. TechCrunch noted that Instinct has disclosed no user count, no revenue, no pricing, and no date for a public launch. The Information has reported that Instinct has told users it’s running at full capacity — a sign demand is already outpacing supply. The company has just 14 employees.