{"slug": "meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut", "title": "Meta AI Researcher Andrew Tulloch Exits Days After Muse Assistant Debut", "summary": "Meta AI researcher Andrew Tulloch is leaving the company days after Meta unveiled Muse, its new family of open source AI models and assistant, according to Semafor, which cited a person briefed on the matter. Tulloch, who rejoined Meta in October 2025 from Thinking Machines Lab after an 11-year earlier stint at Meta and a stop at OpenAI, delayed his exit until the Muse release shipped. Meta has not publicly addressed the departure, and it is unclear why he left the TBD Lab unit led by Scale AI founder Alexandr Wang.", "body_md": "Meta AI researcher Andrew Tulloch is leaving the company just days after it rolled out its newest consumer products, according to Semafor, which cited a person briefed on the matter. Tulloch reportedly held off on his exit until Meta finished shipping the release, timing that suggests the departure had been in motion for some time even as he stayed on to see the launch through. The move adds another name to the list of high-profile researchers cycling in and out of Meta’s AI division over the past year.\n\nThe product Tulloch waited for was Muse, a new family of open source AI models paired with an AI assistant that Meta unveiled this week. Muse is built to go beyond answering questions, connecting to a user’s email, calendar, and other personal accounts so it can take actions on their behalf, and Meta leaned heavily on security messaging in its rollout, using the word “secure” eleven times in the announcement. Whether that pitch lands with Meta’s roughly 3.6 billion daily users will determine if Muse becomes the company’s breakout consumer AI product or another release that fails to stick.\n\nTulloch’s exit is notable given how recently he arrived. He joined Meta’s TBD Lab, the unit at the center of CEO Mark Zuckerberg’s AI strategy and led by Scale AI founder Alexandr Wang, after departing Thinking Machines Lab, the startup he co-founded with former OpenAI CTO Mira Murati. His hire was widely covered because of the size of the compensation package Meta reportedly offered to bring him over, and his departure now raises fresh questions about turnover inside one of Meta’s most closely watched AI teams.\n\n## Why Tulloch’s Departure Stands Out\n\nTulloch’s career path has made him one of the more closely tracked figures in the current AI talent market. He spent 11 years at Meta earlier in his career before leaving for OpenAI, then helped Mira Murati launch Thinking Machines Lab in February, a startup that raised roughly $2 billion and built out a 30 person team. He left that startup last October to rejoin Meta, a move the Wall Street Journal reported came with a compensation package that could have been worth up to 1.5 billion dollars over at least six years, a figure Meta called inaccurate at the time.\n\n### A Pattern of Rapid Moves\n\n| Period | Move | Reported Detail | \n|---|---|---|\n| Career start through OpenAI stint | 11 years at Meta, then OpenAI | Early tenure before startup detour | \n| February 2025 | Co-founded Thinking Machines Lab with Mira Murati | Startup raised about $2 billion, built a 30 person team | \n| October 2025 | Left Thinking Machines Lab to rejoin Meta | WSJ reported a package worth up to $1.5 billion over six years | \n| September 2026 | Departs Meta after Muse launch | Delayed exit until Muse shipped, per Semafor | \n\n### What Meta Has Said\n\nMeta has not issued a public statement addressing Tulloch’s departure, and it remains unclear why he left the TBD Lab or whether he plans to continue AI research elsewhere. That silence is consistent with how the company handled his arrival, when a spokesperson pushed back on reporting about his pay package without offering an alternative figure.\n\n## The Broader Context Around Muse\n\n### What Muse Is Built to Do\n\nMuse represents a shift for Meta AI from a chat based assistant to one designed to act on a user’s behalf, similar in spirit to the agentic tools other AI labs have been building into coding assistants. Giving an assistant access to email, calendars, and health information raises the stakes on trust, which is likely why Meta’s announcement repeated assurances about security so heavily.\n\n#### Talent Churn at Meta’s AI Labs\n\nTulloch’s exit follows a period of aggressive recruiting by Meta, which restructured its AI efforts into a Superintelligence Lab and made large compensation offers to pull in researchers from rival labs. A researcher leaving so soon after a marquee product launch is likely to draw scrutiny over whether Meta’s AI division can retain the talent it spent heavily to acquire, even as the company continues to compete with OpenAI, Google DeepMind, and Anthropic for both people and product wins.\n\nMeta AI’s next moves, including how Muse performs with the public, may shape whether more departures follow or whether the company’s spending on talent starts to translate into a more stable research bench.", "url": "https://wpnews.pro/news/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut", "canonical_source": "https://www.kobaran.com/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut/", "published_at": "2026-09-10 00:01:37+00:00", "updated_at": "2026-09-10 00:50:27.963440+00:00", "lang": "en", "topics": ["artificial-intelligence", "ai-products", "ai-startups", "generative-ai", "ai-agents"], "entities": ["Meta", "Andrew Tulloch", "Muse", "Semafor", "TBD Lab", "Alexandr Wang", "Thinking Machines Lab", "Mira Murati"], "alternates": {"html": "https://wpnews.pro/news/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut", "markdown": "https://wpnews.pro/news/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut.md", "text": "https://wpnews.pro/news/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut.txt", "jsonld": "https://wpnews.pro/news/meta-ai-researcher-andrew-tulloch-exits-days-after-muse-assistant-debut.jsonld"}}