# Researchers can now reverse-engineer LLM prompts from output text with near-perfect accuracy

> Source: <https://the-decoder.com/researchers-can-now-reverse-engineer-llm-prompts-from-output-text-with-near-perfect-accuracy/>
> Published: 2026-08-12 17:32:59+00:00

Researchers at IIT Bombay and Adobe Research have built an inverse language model that reconstructs the original prompt from an LLM's output with near-perfect accuracy. Their method, called "Previous-Token Prediction," doesn't need access to model weights and works across different models. For companies relying on proprietary system prompts, this could be a serious security risk.

The article [Researchers can now reverse-engineer LLM prompts from output text with near-perfect accuracy](https://the-decoder.com/researchers-can-now-reverse-engineer-llm-prompts-from-output-text-with-near-perfect-accuracy/) appeared first on [The Decoder](https://the-decoder.com).