# What is data leakage, and what are real-world examples?

_Last updated: 2026-07-20_  
_Reviewed by: Jason Burns, Editorial Steward_  
_Published by: AIDirectAnswers.com · Licensed under Citation License 1.0_

## Short answer

Data leakage in machine learning is the accidental inclusion of information in training data that would not be available at prediction time, causing models to look good in evaluation and fail in production.

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_Author: [Jason Burns](https://www.linkedin.com/in/jason-randolph-burns), Editorial Steward_  
_Published: 2026-07-20 · Modified: 2026-07-20_  
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