# Recital (128)

In line with the commonly established notion of substantial modification for products regulated by Union 
harmonisation legislation, it is appropriate that whenever a change occurs which may affect the compliance of 
a high-risk AI system with this Regulation (e.g. change of operating system or software architecture), or when the 
intended purpose of the system changes, that AI system should be considered to be a new AI system which should 
undergo a new conformity assessment. However, changes occurring to the algorithm and the performance of AI 
systems which continue to ‘learn’ after being placed on the market or put into service, namely automatically 
adapting how functions are carried out, should not constitute a substantial modification, provided that those 
changes have been pre-determined by the provider and assessed at the moment of the conformity assessment.

---
Source: Regulation (EU) 2024/1689 (Artificial Intelligence Act) as amended by Regulation (EU) 2026/1744, consolidated text of 27 July 2026 (Official Journal of the EU). This page is AI-generated legal information, not legal advice. Verify against the Official Journal.
Canonical: https://euaiactlaw.com/recital/128