Ineffable Intelligence, the London-based AI startup started by former Google DeepMind reinforcement learning chief David Silver, has added six new “cofounders” to its ranks, according to a report from Fortune. Four of the six come from Google DeepMind, continuing a trend of senior researchers leaving the Alphabet-owned lab for rival AI ventures.
The four ex-DeepMind hires are Chris Apps, Wojciech Czarnecki, Lasse Espeholt, and Junhyuk Oh. Apps, Czarnecki, and Oh all worked directly with Silver on AlphaStar, DeepMind’s 2019 system that learned to beat top human players at the real-time strategy game StarCraft II. Espeholt, meanwhile, previously worked on Google’s MetNet weather-forecasting models.
The fifth new cofounder is Alexandre Laterre, who was head of research at InstaDeep, the London AI company that was bought by BioNTech in 2023. The sixth is Heather Gorham, a former partner at venture firm Flying Fish, which was among Ineffable’s earliest backers. All six have updated their LinkedIn profiles to reflect the new titles, and Ineffable confirmed the hires without further comment.
At Ineffable, Oh will lead reinforcement learning work — a fitting assignment given he was the reinforcement learning lead on AlphaStar and was, in 2025, among the first researchers to use AI to discover new reinforcement learning algorithms of its own. That focus on automating RL research dovetails with the broader industry push toward “recursive self-improvement,” where AI systems help build better versions of themselves with minimal human input.
Czarnecki, who worked on multi-agent research at DeepMind including its capture-the-flag AI agents, will run Ineffable’s science team. Apps, who worked as a technical program and research delivery lead at DeepMind after stints at Barclays and Deloitte, will head “mission acceleration.” Espeholt takes charge of compute, infrastructure, and engineering strategy, while Laterre will oversee research engineering.
Gorham’s role covers compute, fundraising, and operations. As a Flying Fish partner, she had reportedly approached Silver back in early 2024 to discuss new approaches to reinforcement learning, positioning her firm to write the first check when he eventually left DeepMind to start his own company. That early bet paid off: Flying Fish went on to participate in Ineffable’s $1.1 billion seed round, the largest ever raised by a European startup, which valued the company at $5 billion. Gorham is also said to have helped secure Ineffable’s Google Cloud computing partnership, announced in July.
The hiring spree adds to a broader wave of senior researchers exiting Google DeepMind for competing labs and startups in recent months, feeding a narrative that the pioneering AI lab is losing ground to a new generation of well-funded rivals. Ineffable is among the “neolabs” — new frontier AI companies founded in the past two years by veterans of DeepMind, OpenAI, and Anthropic, alongside the likes of Mira Murati’s Thinking Machines Lab and Ilya Sutskever’s Safe Superintelligence.
Unlike many of those peers, Ineffable has staked its approach to superintelligence specifically on reinforcement learning — the trial-and-error training method Silver is best known for from his work on AlphaGo, AlphaZero, and AlphaStar, rather than the large language model scaling that dominates the rest of the industry. The company’s stated ambition is to build a “superlearner” capable of discovering knowledge entirely from its own experience, without relying on human-generated data.
Notably, the Fortune report also sheds some light on the company’s murky origins. Ineffable’s Companies House filings show it was actually incorporated in November 2025 by Canadian entrepreneur George “Geordie” Rose, with Silver only becoming a director in January 2026 after officially leaving DeepMind. Rose stepped down as a director in July and now lists himself as a “founding advisor,” with an Ineffable spokesperson clarifying that Silver does not consider him a cofounder.