Meta, parent company of Facebook and Instagram, is challenging the UK media regulator Ofcom in the High Court over fees and potential fines introduced under the Online Safety Act.

The law, which came into force in July 2025, introduced protections against harmful online content, with Ofcom’s operating costs for carrying out its online safety work funded by tech firms.

Under regulations introduced in September, the fees are based on a company’s qualifying worldwide revenue and apply to firms earning more than £250m a year.

Meta said Ofcom’s methods for calculating fees and penalties were “disproportionate”, while Ofcom said it would “robustly defend” its position.

Meta is challenging rules covering search engines and platforms where users can share content, including social media sites.

Lawyers acting for the company argue the regulations are unlawful and should be reconsidered by the regulator.

Monica Carss-Frisk KC, for the tech giant, has said in court documents that Ofcom’s approach is “troubling” and leads to “a handful of companies, such as Meta, bearing the vast majority of Ofcom’s costs, despite the act making clear that it is concerned with a wide range of internet services offered in the UK”.

She also argued the calculation of qualifying worldwide revenue was not linked specifically to earnings from UK services.

Under the Online Safety Act, companies found to have breached safety rules can face fines of up to 10% of qualifying worldwide revenue or £18m, whichever is greater.

Meta is also disputing how penalties are calculated when multiple companies owned by the same parent organisation are found jointly liable for breaches.

At a preliminary hearing in London on Thursday, the High Court heard Fortnite-maker Epic Games and the trade body the Computer and Communications Industry Association are expected to seek permission to intervene in the case.

Mr Justice Chamberlain said the dispute raised issues “of wide public importance” and confirmed the next hearing would take place in June.

A full hearing is expected in October.

Wikipedia lost its own legal challenge against the Online Safety Act last August over age verification requirements.

An Ofcom spokesperson said the regulator had based its approach on “a plain reading of the law”.

“Disappointingly, Meta are objecting to the payment of fees, and any penalties that could be levied on companies in future, that are calculated on this basis,” the spokesperson said.

A Meta spokesperson said the firm remains “committed to co-operating constructively with Ofcom as it enforces the Online Safety Act”.

The spokesperson said penalties should instead be based on the revenues generated by the services being regulated in the countries where they operate.

“This would still allow Ofcom to impose the largest fines in UK corporate history,” they added.

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