Ineffable
formerly Ineffable IntelligenceBuilding AI that discovers all knowledge from its own experience
London, United Kingdom · Founded 2025 · $1.1B raised
- Headquarters
- London
- Employees
- 1–10
- Founded
- 2025
- Business Model
- B2B
- Website
- ineffable.ai
- Total Funding
- $1.1B
- Last Round
- $1.1B SeedApr 2026
- Rounds
- 1
Totals include recorded grants and other qualifying funding, not just equity. What counts toward funding.
About
Ineffable Intelligence is a London-based AI lab founded by former Google DeepMind researcher David Silver, creator of AlphaZero, aiming to build a 'superlearner' AI capable of discovering knowledge and skills without relying on human data, using reinforcement learning. The company raised $1.1 billion at a $5.1 billion valuation in a round led by Sequoia Capital and Lightspeed Venture Partners, with participation from Index Ventures, Google, Nvidia, the British Business Bank, and others.
Summary
Ineffable is an Artificial Intelligence company based in London, United Kingdom, founded in 2025. It has raised $1.1B in total across 1 round, most recently a $1.1B Seed round in Apr 2026. Investors include Alphabet, Sequoia Capital and Lightspeed Venture Partners.
Tech & App Stack
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Funding History
Apr 2026
Investors
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