Index AI builds the data infrastructure that trains the world's most capable models — autonomous synthesis pipelines, rigorous quality frameworks, and RL post-training data engineered by the people who built Gemini.
Founded & backed by alumni of
// About
Frontier models are only as good as the data behind them. Index AI is a data company in the deepest sense — we design, synthesize, verify and deliver the high-fidelity training data that determines whether a model merely answers, or truly reasons.
// Business Units
Four business units, one mission: supply frontier models, world models and AI-for-Science with the highest-fidelity data on earth.
End-to-end, autonomous data synthesis pipelines with rigorous quality-assurance frameworks — consistently supplying models with high-fidelity training data at scale.
synthesis · verification · scaleValue functions, step-level reward mechanisms and credit-assignment solutions for long-horizon reasoning — the post-training layer that turns base models into reasoners.
RLHF · reward models · reasoningMulti-step planning engines and multimodal agentic data — purpose-built for the world model companies defining the next paradigm of AI.
agents · planning · multimodalHigh-fidelity data for scientific foundation models — research corpora, simulation and experimental datasets that power AI-driven discovery across the sciences.
science · simulation · discovery// Founders
Our founding team comes from the labs and companies defining this era of AI — Google DeepMind, OpenAI, Anthropic, Stanford and TikTok.
The founding team includes core contributors to the Gemini model ecosystem at Google DeepMind, with deep expertise in Large Language Models — particularly data strategy and Reinforcement Learning (RL) post-training — alongside founders with research and operating backgrounds spanning OpenAI, Anthropic, Stanford and TikTok.
Together, the team has architected end-to-end, autonomous data synthesis pipelines and rigorous quality-assurance frameworks to consistently supply models with high-fidelity training data, and driven critical advancements in value functions and step-level reward mechanisms to resolve complex credit-assignment challenges in long-horizon reasoning tasks.
Beyond these core areas, their work extends to spearheading multi-step planning engines for multimodal agentic systems.
// Team
Researchers, engineers and operators from the organizations that defined modern AI and modern technology companies.
Core contributors to the Gemini model ecosystem — LLM data strategy, RL post-training, and reward modeling.
Teammates who researched and shipped frontier model systems at OpenAI, across training and deployment.
Stanford postdoctoral researcher specializing in reinforcement learning and inference.
Engineers who shipped planet-scale infrastructure and enterprise-grade platforms trusted by billions.
Operators who built consumer products that scaled to hundreds of millions of users worldwide.
YC alumni with the pattern-recognition and velocity of Silicon Valley's most iconic accelerator.
Financial leaders with deep expertise in venture capital, startup banking and capital strategy.
Research rigor, engineering excellence and operating discipline — under one roof, pointed at data.
// Partners
The next paradigm of AI is models that understand and simulate the world. Index AI partners with leading labs and stealth teams to supply the data layer this future is built on.
Domains we serve
// Contact
Whether you're training a frontier model, a world model, or an agentic system — the data layer decides how far you go. Let's talk.