What Is Substantial Modification?
Substantial Modification is a change to a high-risk AI system, or a use beyond its intended purpose, significant enough to trigger fresh obligations under the EU AI Act.
Substantial Modification — a change to a high-risk AI system, or a use beyond its intended purpose, significant enough to trigger fresh obligations under the EU AI Act.
The EU AI Act allocates duties between providers and deployers, but those roles can shift. If a deployer substantially modifies a high-risk system, or puts their own name on it or uses it for a purpose it was not designed for, they can take on the heavier provider obligations themselves (Article 25). It is a key trap for organisations that fine-tune or repurpose third-party AI.
Source: EU AI Act, Article 25
Plain-language explanation
The EU AI Act allocates duties between providers and deployers, but those roles can shift. If a deployer substantially modifies a high-risk system, or puts their own name on it or uses it for a purpose it was not designed for, they can take on the heavier provider obligations themselves (Article 25). It is a key trap for organisations that fine-tune or repurpose third-party AI.
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