The Wikimedia Foundation is challenging the United Kingdom’s Online Safety Act after it reportably may be affected by its Categorisation regulations.
On 8 May, 2025, the Wikimedia Foundation announced that it is challenging the lawfulness of a new element of the UK’s Online Safety Act (OSA) that determines what duties a website has under the law. This legal challenge is a last resort. It comes after years of sharing our concerns with UK policymakers that these measures — meant to improve online safety on major commercial platforms — could have detrimental consequences for public interest platforms like Wikipedia. These concerns remained unaddressed. We are taking action now to protect Wikipedia users, as well as the global accessibility and integrity of free knowledge.
As a Category 1 service, Wikipedia may be considered a platform that poses the highest possible level of risk to the public. As a nonprofit, the Wikimedia Foundation is concerned that it can’t handle the fiscal burdens associated with strict reporting and compliance mandates. This is an obligation normally affecting large social media platform rather than a free encyclopedia service.
The Foundation is challenging the OSA’s Categorisation Regulations, which are written broadly enough that they could place Wikipedia as a “Category 1 service” — a platform posing the highest possible level of risk to the public.
This determination is made based on broadly-drafted criteria about the number of visitors to a website and certain basic organizational features, like the ability to forward content. As a Category 1 service, Wikipedia could face the most burdensome compliance obligations, which were designed to tackle some of the UK’s riskiest websites.