The Amsterdam Court's preliminary injunction, which could set a precedent in Europe, is one of the first times a judge has weighed in on xAI's responsibility for making tools that can be used to easily create sexualised images, amid a flood of complaints and investigations over Grok around the world.
In a written decision on Thursday, the court said xAI and Grok would be prohibited from "generating and/or distributing sexual imagery ... whereby persons are partially or wholly stripped naked without having given their explicit permission" and it would impose fines of 100,000 euros ($A166,500) per day if the companies do not comply.
It also ordered xAI not to offer Grok on X while in breach of the order.
The case was brought by Offlimits, a Dutch non-profit group that combats online sexual abuse, in cooperation with the nonprofit Victims Support Fund.
A lawyer for xAI in the Netherlands referred questions to xAI. xAI did not respond to requests for comment.
At a hearing earlier in March, xAI argued it could not stop all abuse of its tools and should not be penalised for the actions of malicious users.
Its lawyers said the company tightened safeguards in January to stop Grok from editing images of real people into revealing clothing, including by restricting image generation to paid subscribers.
Offlimits director Robbert Hoving said judges had rejected that as insufficient after a March 9 courtroom demonstration showed Grok was still able to "undress" digital images of people without their consent.
"The burden is on the company" to make sure its tools are not used to make non-consensual sexual images, or sexualised AI images of children, Hoving said.
The ruling comes as European regulators step up scrutiny of Grok and other AI tools under the EU's Digital Services Act, which requires major platforms to curb illegal content.
The European Commission opened a formal probe into X in January over risks tied to Grok's rollout in the EU, including manipulated sexually explicit images.
On Thursday, the European Parliament also backed a ban on AI "nudifier" apps that create or manipulate sexually explicit images.
