The Wikimedia Foundation, the non-profit organization that operates Wikipedia, has lost a legal challenge against the United Kingdom’s Online Safety Act (OSA), raising concerns about the future accessibility of the online encyclopedia and the privacy of its volunteer editors in the UK.

In a ruling issued Monday, the High Court of Justice dismissed Wikimedia’s judicial review request, which sought to contest how the UK government and communications regulator Ofcom had categorized Wikipedia under the new law.

The foundation had argued that placing Wikipedia under the law’s Category 1 designation, a classification intended for the largest and most interactive online platforms, was “illogical” and would impose unreasonable and damaging obligations on the platform.

Category 1 services under the OSA face the most stringent duties, including mandatory identity verification of users and contributors, content moderation requirements, and the potential disclosure of user data to authorities. Wikimedia has repeatedly warned that such obligations could compromise the safety and privacy of its contributors, many of whom write anonymously.

“While the decision does not provide the immediate legal protections for Wikipedia that we hoped for, the Court’s ruling emphasized the responsibility of Ofcom and the UK government to ensure Wikipedia is protected as the OSA is implemented,” Wikimedia said in a statement.

If the UK classifies Wikipedia as a Category 1 platform and enforcement proceeds as currently outlined, the Wikimedia Foundation has said it may be forced to block access to Wikipedia in the UK or cut access for up to three-quarters of UK users to avoid the most burdensome regulatory requirements.

Judge Jeremy Johnson, who issued the ruling, acknowledged the platform’s concerns and stated that the decision “does not give Ofcom and the Secretary of State a green light to implement a regime that would significantly impede Wikipedia’s operations.”

He further clarified that Wikimedia could bring additional legal challenges in the future, particularly if Ofcom moves forward with a formal Category 1 designation.

The UK government welcomed the ruling. A spokesperson for the Department for Science, Innovation and Technology stated,

“This judgment will help us continue our work implementing the Online Safety Act to create a safer online world for everyone.”

Ofcom, which is charged with enforcing the new regulations, said it would “continue to progress our work in relation to categorised services and the associated extra online safety rules.”

The Online Safety Act, which became law in 2023 and is being phased in throughout 2024–2025, has drawn criticism from free speech advocates, civil rights organizations, and tech companies. Critics argue the law is overly broad, risks stifling legal content, and may impose disproportionate obligations on platforms that are not traditional social media services.

“Wikipedia has been caught in the stricter regulations due to its size and user-created content, even though it differs significantly from other user-to-user platforms,” said Mona Schroedel, a litigation expert with UK law firm Freeths.

“The court’s decision has left the door open for Wikipedia to be exempt from the stricter rules upon review.”

Social media company X (formerly Twitter) has also publicly opposed the Online Safety Act, claiming it requires “significant changes” to avoid chilling effects on speech.

While the Wikimedia Foundation’s current legal challenge has been dismissed, the organization may pursue future challenges if Ofcom proceeds with a final classification or if enforcement under the OSA begins to hinder Wikipedia’s operations directly.

“The foundation will continue to seek solutions to protect Wikipedia and the rights of its users as the OSA continues to be implemented,” the organization said.

For now, Wikipedia remains accessible in the UK, but its long-term future in the region—and the freedom of its volunteer editors—remains uncertain under the evolving regulatory landscape.