David Silver, the ex-Google DeepMind researcher who helped build the AI that crushed humanity’s best StarCraft II players, is assembling what looks like an AI Avengers roster. His London-based startup Ineffable Intelligence has brought on six new “cofounders,” pulling senior talent from DeepMind, InstaDeep, and Flying Fish to chase an absurdly ambitious goal: building what the company calls a “superlearner.”
The hiring spree comes after Ineffable closed a $1.1 billion seed round, the largest seed financing in European startup history, giving the pre-revenue company a $5.1 billion valuation.
The team behind the team
Four of the six new cofounders are former DeepMind colleagues of Silver’s. Chris Apps, Wojciech Czarnecki, and Junhyuk Oh all worked with Silver on AlphaStar, the 2019 AI system that achieved grandmaster-level play in StarCraft II, a game so strategically complex that it was considered a frontier challenge for artificial intelligence at the time.
The fourth DeepMind alumnus, Lasse Espeholt, took a different path at Google. He helped build MetNet, Google’s weather prediction AI models that pushed the boundaries of what machine learning could do with atmospheric data.
The fifth cofounder, Alexandre Laterre, served as head of research at InstaDeep, a London-based AI company that BioNTech acquired in 2023. That acquisition married InstaDeep’s reinforcement learning expertise with BioNTech’s vaccine development pipeline.
The sixth cofounder hails from Flying Fish.
What Ineffable is actually building
The company’s core thesis is a departure from the dominant playbook in AI development. Instead of training models on massive datasets scraped from the internet, Ineffable wants its AI to learn through trial and error in simulated environments. This approach, large-scale reinforcement learning, is the same methodology that powered AlphaStar and DeepMind’s earlier AlphaGo breakthrough. Silver was a lead researcher on both projects.
Silver incorporated Ineffable Intelligence in November 2025 and left DeepMind in January 2026 to lead the company full-time. The startup emerged from stealth on April 27, 2026, when it announced the funding round.
The money and the backers
Sequoia Capital and Lightspeed Venture Partners co-led the $1.1 billion round. The investor list also includes Nvidia, Google, and Index Ventures, alongside UK government entities including the Sovereign AI Fund and British Business Bank.
One unusual wrinkle: Silver has pledged to donate 100% of his equity proceeds from Ineffable to high-impact charities.