Scale AI

Scale AI is an American artificial intelligence infrastructure and software company based in San Francisco, California. It was originally focused on data annotation, and it also offers RLHF services, large language model (LLM) evaluation, and enterprise software suites. It outsources data labeling through two subsidiaries, Remotasks, which focuses on computer vision and autonomous vehicles, and Outlier, which focuses on annotating data for LLMs.

Scale was founded in 2016 by Alexandr Wang and Lucy Guo through Y Combinator. Its headquarters are in San Francisco, and it reports more than 1,000 employees. In June 2025, Meta Platforms spent more than $14 billion to acquire a 49% non-voting stake in Scale AI. Alexandr Wang left as CEO to join Meta and was replaced by Jason Droege. Its commercial customers have included Google, Microsoft, Meta, General Motors, OpenAI, and Time.

Scale AI runs an LLM Red Team that conducts human adversarial testing to identify vulnerabilities, biases, and safety risks in AI models. The team has worked with OpenAI, Google DeepMind and national AI Safety Institutes. Its research arm, the Safety, Evaluation and Alignment Lab, focuses on evaluating and aligning LLMs.