Ineffable Intelligence, a British AI lab founded by former DeepMind researcher David Silver, raised $1.1 billion in April 2026 at a valuation of $5.1 billion — just months after the company was established.
The round was led by Sequoia Capital and Lightspeed Venture Partners, with participation from Index Ventures, Google, Nvidia, the British Business Bank, and Sovereign AI, the U.K.’s recently launched sovereign venture fund for AI.
Ineffable’s stated goal is to build a “superlearner” — an AI capable of discovering knowledge and skills without relying on human-generated data. The approach centers on reinforcement learning, a technique in which AI systems learn through trial and error rather than studying human examples. Silver spent more than a decade leading the reinforcement learning team at Google-owned DeepMind before departing to found Ineffable. He is also a professor at University College London.
At DeepMind, Silver was involved in developing AlphaZero and related programs that beat professional players at chess and Go by learning purely from self-play, without being fed human strategies or game records. Ineffable aims to apply a similar principle at a broader scale. The company’s website states: “If successful, this will represent a scientific breakthrough of comparable magnitude to Darwin: where his law explained all Life, our law will explain and build all Intelligence.”
Silver has described Ineffable as “his life’s work” and told Wired that any personal earnings from the company will go to high-impact charities. The company has not disclosed how or when it plans to generate revenue.
The raise brings Ineffable into a growing cluster of well-funded AI ventures with roots in London. Other recent examples include Recursive Superintelligence, co-founded by former DeepMind principal scientist Tim Rocktäschel, which reportedly raised $500 million, and AMI Labs, co-founded by Turing Award winner Yann LeCun, which raised $1.03 billion last month. Jeff Bezos’ AI lab, Project Prometheus, is also reportedly in talks to secure office space near Google’s London AI hub.
Source: TechCrunch