What obligations does the provider of an AI system have under Article 20 of the AI Act?

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• Applies to providers of high-risk AI systems as soon as they consider, or have reason to consider, that a system they have placed on the market or put into service is not in conformity with this Regulation. For the standalone Annex III route (Article 6(2)) the date is 2 December 2027. For systems embedded as a safety component in products covered by the Annex I harmonisation legislation (Article 6(1)) the date is 2 August 2028.
• The second layer in paragraph 2 is added only where the system presents a risk within the meaning of Article 79(1) and the provider becomes aware of that risk. The investigation of causes and the duty to inform the market surveillance authorities and, where applicable, the notified body that issued a certificate under Article 44, then come on top of the corrective actions under paragraph 1.
• The distributor, the importer and the deployer appear here as affected parties, but that is not their only possible position. Anyone who puts their name or trade mark on a high-risk system already placed on the market, who substantially modifies such a system, or who changes the intended purpose of a system not classified as high-risk so that it becomes high-risk, is considered a provider under Article 25(1) and is subject to the obligations of Article 16. Point (j) of that Article routes straight to Article 20, so this provision then becomes a duty of their own rather than a notification arriving from someone else. In the trade mark case this applies without prejudice to contractual arrangements allocating the obligations otherwise.
• Article 20 is by definition about systems already placed on the market or put into service, and that is exactly the group covered by the transitional rule of Article 111(2). That provision was replaced by Article 1, point (39)(a), of Regulation (EU) 2026/1744 and now reads: without prejudice to the application of Article 5 as referred to in Article 113, third paragraph, point (a), this Regulation applies to operators of high-risk AI systems, other than the systems referred to in paragraph 1 of that Article, that have been placed on the market or put into service before the date of application of Chapter III referred to in Article 113, only if, as from that date, those systems are subject to significant changes in their designs. The cut-off is therefore no longer a fixed date in paragraph 2: the date of 2 August 2026 that stood there until that amendment has been removed, and the amended paragraph names no date of its own. The carve-out in paragraph 1 covers systems that are components of the large-scale IT systems listed in Annex X; paragraph 1 was not amended and keeps a cut-off of its own. For systems intended to be used by public authorities the reprieve in paragraph 2 does not hold: there, compliance with the requirements and obligations is due by 2 August 2030 in any event. Which date of application of Chapter III is the cut-off is an open point: the object on Article 111 reads it as route dependent, so 2 December 2027 for the Annex III route and 2 August 2028 for the Annex I route, and marks that reading expressly as preliminary. That question is carried there, not here.