Ineffable Intelligence, the London-based AI startup launched earlier this year by former Google DeepMind researcher David Silver, has added six high-profile "cofounders" to its ranks. Silver is one of the most prominent figures in reinforcement learning, having been a key architect of DeepMind's AlphaGo—the system that defeated world Go champion Lee Sedol in 2016—as well as the later, more general AlphaZero, making his hires a signal of the research directions the startup intends to prioritize.

Four of the new hires are former Google DeepMind colleagues of Silver's: Chris Apps, Wojciech Czarnecki, Lasse Espeholt, and Junhyuk Oh. Apps, Czarnecki, and Oh all worked with Silver on DeepMind's 2019 AlphaStar breakthrough—an AI system capable of defeating the world's best human players at StarCraft II, the competitive real-time strategy video game. Espeholt, for his part, helped build Google's MetNet weather prediction AI models.

The fifth cofounder, Alexandre Laterre, previously served as head of research at London-based AI company InstaDeep, which was acquired by biotech company BioNTech in 2023. The sixth, Heather Gorham, was a partner at venture capital firm Flying Fish, one of Ineffable's earliest investors. All six have recently updated their LinkedIn profiles to reflect their new roles. Ineffable confirmed the hires but declined to comment further.

In April, Ineffable was valued at $5 billion when it raised a $1.1 billion seed round of venture capital funding—the largest seed investment ever made in Europe. The round reflects how aggressively investors have been backing new frontier AI ventures even before they have shipped products, and it gives the young company the resources to compete for scarce top-tier research talent. The hiring spree adds to the wave of high-profile researchers who have recently left Google DeepMind to join rival AI companies, a trend that has contributed to a perception that DeepMind—the first company to make the creation of AI models rivaling or exceeding human intelligence its primary mission—is now struggling.

Records at U.K. business registry Companies House show that when Ineffable was incorporated in November 2025, it was set up by George "Geordie" Rose, a Canadian serial entrepreneur and tech investor. Silver only became a company director in January 2026, after he officially departed DeepMind. Companies House records show that one month later, Rose was no longer a "person with significant control" of Ineffable's shares, and he stepped down as a director in July. Rose's LinkedIn profile and web page list him as a "founding advisor" to the company. A company spokesperson said Rose is a friend of Silver's who helped get the company up and running before moving into an advisory role, but that Silver does not consider him a "cofounder."

Ineffable is one of the so-called "neolabs"—a next generation of frontier AI companies launched over the past two years, many of them started by veterans of the three older companies whose goal was the creation of advanced artificial intelligence: Google DeepMind, OpenAI, and Anthropic. Beyond Ineffable, the neolabs include Thinking Machines Labs, cofounded by former OpenAI chief technology officer Mira Murati; Safe Superintelligence, cofounded by former OpenAI chief scientist Ilya Sutskever; as well as Sakana AI, Recursive Superintelligence, Core Automation, and Adaption Labs, among others.

Like other neolabs, Ineffable's stated mission is to create AI superintelligence. But the company is committed to getting there through reinforcement learning, the AI training technique with which Silver is closely associated. In reinforcement learning, an AI model learns by trial and error to maximize a reward established by the person training the model—somewhat similar to operant conditioning in psychology, where actions that lead to rewards are reinforced and agents learn not to repeat those that don't. The technique was also foundational to many of DeepMind's landmark achievements, including AlphaGo and AlphaZero.

Oh, who will run reinforcement learning at Ineffable, was the reinforcement learning lead on DeepMind's AlphaStar work. In 2025, he was also one of the first researchers to use AI to discover new reinforcement learning algorithms. Using AI to help automate AI research itself is a major focus among frontier AI companies, many of which are pushing toward "recursive self-improvement," or RSI—a point at which AI systems can autonomously optimize future versions of themselves with little to no human help. Oh's hiring suggests Ineffable will also look to use automated reinforcement learning research to accelerate its quest for superintelligence.

At DeepMind, Czarnecki focused on multi-agent research—scenarios in which multiple AI agents must learn to cooperate or compete on various tasks. He also worked on AlphaStar, as well as on DeepMind's research into teams of AI agents that had to learn to work together to beat other AI agents in simulated games of capture the flag held inside virtual mazes. At Ineffable, Czarnecki will oversee the startup's science team.

Apps was a technical program and research delivery lead at Google DeepMind, where he helped project manage the large research teams behind many of the company's breakthroughs. Before DeepMind, he helped run technology transformation programs at Barclays bank and Deloitte. He will lead "mission acceleration" at Ineffable.

According to his LinkedIn profile, Espeholt will be in charge of Ineffable's "compute, infrastructure, and engineering strategy," while Laterre will oversee research engineering. Gorham, according to her LinkedIn profile, is working on Ineffable's "compute, fundraising, and operations." As a partner at Flying Fish, she approached Silver in early 2024 to learn more about new approaches to reinforcement learning and to lay the groundwork for Flying Fish getting in on the ground floor if Silver ever decided to leave DeepMind and start his own company, according to a GeekWire story. Her efforts paid off: Flying Fish wrote the first check for Silver's new company and played a role in its mega seed round, which was led by Sequoia and Lightspeed Ventures. Gorham also helped secure Ineffable's computing power partnership with Google Cloud, announced in July.

This story was originally featured on Fortune.com.