Instinct raised $1 billion in a Series C round this week at a $10 billion valuation, sharply increasing the value of the invite-only personal-assistant startup founded by 23-year-old Noah Shinn. The financing followed a $250 million raise at a $2.5 billion valuation in August, bringing the company’s total funding at that time to $350 million. Shinn said on the Invest Like the Best podcast that Instinct is approaching $1 billion in annual transaction volume, with travel accounting for about half of that activity. The free assistant communicates by message or phone call and has spread largely through word of mouth despite spending nothing on marketing, with users reportedly selling invitations on eBay. Instinct opened an invite-only beta last month after launching a private beta in February, and each user received five invitations. Shinn said the platform is growing 10% daily and could simplify travel and restaurant reservations by remembering user preferences and acting on their instructions. The 14-member startup competes with Meta’s Muse and Khosla-backed Wajo, while Meta chief AI officer Alexandr Wang has publicly mocked Instinct in posts that generated hundreds of thousands of views. Muse recently became the top free app on the U.S. App Store and recorded 2.8 million worldwide installs in its first 12 days, according to Apptopia estimates cited by TechCrunch. Shinn, who left Northeastern University in 2023 and previously worked at AI startup Sierra, co-authored the influential Reflexion paper on language agents and verbal reinforcement learning.