xai
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Eric Zelikman
Eric Zelikman is the co-founder and CEO of humans&, a human-centric frontier AI lab in Redwood City building foundation models designed for communication and collaboration rather than automation. A former early researcher at xAI, he helped shape Grok's pretraining data and scaled reinforcement learning for reasoning across Grok 3 and Grok 4. Before that, as a Stanford PhD candidate, he authored STaR and Quiet-STaR, foundational papers that taught language models to reason in natural language using their own rationales. In January 2026, humans& emerged from stealth with a $480M seed round at a roughly $4.48B valuation, backed by Nvidia, Jeff Bezos, GV, SV Angel and Emerson Collective.
Ying Sheng
Ying Sheng is the co-founder and CEO of RadixArk, an AI infrastructure company that spun out of SGLang, the open-source inference engine she helped create in 2023. SGLang now runs across hundreds of thousands of GPUs and serves trillions of tokens a day for Google, Microsoft, NVIDIA, xAI and others. A Stanford computer science PhD and former xAI technical staff who co-led the inference team behind Grok, she launched RadixArk in May 2026 with $100 million in seed funding led by Accel at a $400 million valuation, on a mission to make frontier-level AI infrastructure open and accessible to everyone.
Elon Musk
Elon Musk is the wealthiest person in recorded history and the founder or co-founder of nine major companies including SpaceX, Tesla, xAI, and Neuralink. Born in Pretoria, South Africa, he taught himself to code at 10, sold his first game at 12, and dropped out of a Stanford PhD after two days to chase the internet gold rush. His companies collectively own 65% of all operational Earth satellites, produce the world's best-selling electric vehicles, and are actively building brain-computer interfaces and rockets to colonize Mars. As of May 2026, his net worth stands at approximately $809 billion.
Shaun Maguire
Shaun Maguire is a partner at Sequoia Capital who bridges the worlds of theoretical physics and venture capital. With a PhD in quantum gravity from Caltech under John Preskill, he co-founded the cybersecurity company Expanse (acquired by Palo Alto Networks for over $1 billion) while completing his doctorate. At Sequoia, he leads investments in deep tech, aerospace, defense, and AI, backing companies like SpaceX, xAI, The Boring Company, and Neuralink. Before Sequoia, he was a partner at Google Ventures, where he led investments in Stripe, IonQ, and Opendoor. His unique background combines rigorous theoretical physics research on multiboundary wormholes with a track record of building and backing billion-dollar companies at the frontier of technology.
Dan Hendrycks
Dan Hendrycks is the Executive Director of the Center for AI Safety (CAIS), the UC Berkeley PhD who created MMLU - the benchmark that shaped how the world measures AI intelligence - and invented GELU, the activation function running inside BERT, GPT, and virtually every major AI model. From a rural evangelical town in Missouri, he's become one of AI safety's most consequential voices, advising Elon Musk's xAI and Scale AI while sounding alarms about civilizational-scale AI risk, accepting $1/year to keep his independence intact.
Christoph Molnar
Christoph Molnar is a Munich-based statistician-turned-ML-author who turned a side project into the field's most-cited book on interpretable machine learning. Author of six books including the canonical 'Interpretable Machine Learning' (3rd ed., 2025), he runs the Mindful Modeler newsletter and consults on making black-box models explainable. With 16,000+ Google Scholar citations and a PhD from LMU Munich, he sits at the precise intersection where statistical rigor meets machine learning pragmatism.
Yao Fu
Yao Fu (符尧) is an AI researcher at xAI specializing in large language model reasoning, efficient inference, and distributed systems. A PhD graduate of the University of Edinburgh, he previously worked at Google DeepMind on Gemini 3 and Project Astra. With over 5,000 citations and key papers like ServerlessLLM (OSDI '24) and DuoAttention (ICLR '25), Fu bridges systems engineering and ML research. He writes the 'Yao Fu' newsletter on Notion and is known for the Chain-of-Thought Hub benchmark repository, which helped track LLM reasoning progress across the field.