EU AI Act Article 5(1)(a) prohibits AI systems that deploy "subliminal techniques beyond a person's consciousness, or purposefully manipulative or deceptive techniques" with the objective or effect of materially distorting the behavior of a person or a group of persons in ways that cause significant harm. Article 5(1)(b) extends the prohibition to systems that exploit vulnerabilities due to age, disability, or specific social or economic situation.
These are categorical prohibitions: systems falling within them cannot be placed on the EU market or put into service. They are the strongest legal expression to date of the principle that AI must not be designed to bypass user autonomy.