Researchers reveal method to extract hidden reasoning from top AI models

A team of researchers has developed a technique to extract hidden reasoning traces from leading AI models, revealing evidence that at least one Chinese AI system may have been trained by distilling insights from American counterparts — though the researchers stress their findings fall short of definitive proof.

Extracting the "Inner Thoughts"

Computer scientists from the University of Tübingen, the Max Planck Institute, the AI safety organization MATS Research, and cybersecurity firm Snyk discovered a vulnerability across models from OpenAI, Anthropic, and Google Alphabet Inc. ↘ 3.61% that allows extraction of concealed reasoning steps — the detailed chain-of-thought processes these systems use to solve complex problems.wired

"All leading frontier model providers we examined exhibit this vulnerability," said Alexander Panfilov, a computer scientist at the University of Tübingen who participated in the research. "This could result in the leakage of personal data and facilitates large-scale reasoning distillation attacks."wired

In their paper, the researchers show that Moonshot AI's open-weight model Kimi K3 produces outputs "remarkably similar" to the hidden reasoning traces of Claude Opus 4.8 and GPT 5.6 Sol for certain prompts. However, they caution that their work "cannot causally establish distillation." The researchers also found that two other open-weight models — China's DeepSeek and US firm Thinking Machines' Inkling — did not show the same reasoning similarity with Claude Opus.wired

Security Flaw and Industry Response

Beyond the distillation question, the technique revealed a security vulnerability that could be exploited to retrieve sensitive information such as passwords and API keys from a model's internal reasoning. Panfilov and his coauthors alerted OpenAI, Anthropic, and Google to the issue, and each company adjusted its API to mitigate the problem. While extracting private information is no longer possible, Panfilov said some reasoning traces can still be uncovered using the method, and fully fixing the distillation risk would require "a fundamental overhaul to the way these companies' APIs work."linkedin

Broader Context

The findings land amid ongoing tensions over AI distillation between US and Chinese firms. In February 2026, Anthropic and OpenAI published evidence of systematic distillation campaigns by Chinese AI companies. More recently, when Moonshot AI released Kimi K3 in July, White House science advisor Michael Kratsios accused the company of copying Anthropic's technology. Independent experts, however, have questioned whether the timeline between Claude's public release and Kimi K3's launch was short enough to support that claim.iaps+2

The new research from Panfilov's team adds a technical dimension to the debate — offering a method that could, in principle, detect distillation at scale — while underscoring how the same transparency tools that advance AI safety may also expose models to competitive extraction.