It's not every day you see three of the world's biggest tech companies - Meta, TikTok, and X - in the same courtroom, on the same side of the argument.
But that's what's happening in the UK, where the three are trying to convince the High Court that the country's speech regulator Ofcom is overstepping its authority.
The court has not ruled yet, but it's already clear that this is a clash of titans. And while the tech companies are trying to defend their own interests, the way the case is framed, and the arguments the court is hearing, might be of interest to their users, as well.
Ofcom is the UK's online speech regulator, and the three companies are accusing it of acting unlawfully and contrary to its own rules.
At the heart of the case are information notices that Ofcom issued in February, under the Online Safety Act, and which the companies are now trying to block.
What Ofcom wants is granular information about content that the platforms remove or restrict, and how many users have been exposed to harmful content before that. Ofcom can fine companies up to 10% of their global turnover.
Meta, that has Facebook, Messenger, Instagram, and WhatsApp under its wing, said Ofcom is asking for "wide-ranging and granular information" about seven of its services, but hasn't explained what regulatory purpose this serves.
Meta said it's more information than it has been asked to provide by any other regulator, around 10,000 extra pieces of information in the first set of requests alone.
"It follows that Ofcom has unlawfully failed to follow its own Section 100 Policy when assessing their proportionality," Meta said. "This constitutes a standalone breach of its public law duties, and one that goes to the heart of its decision-making."
Section 100 of the Act is the power Ofcom has to require companies to provide information, but it must be exercised "in a way that is proportionate to the use to which the information is to be put in the exercise of OFCOM's functions."
And in its own guidance, Ofcom says that "the principle of proportionality is of central importance when exercising our information gathering powers."
But when the companies challenged the notices, Ofcom replied that its policy "does not prescribe a particular document structure, checklist or formula."
TikTok is another company that received a notice from Ofcom in February, and its lawyer, Marie Demetriou, told the court that the requests "circumvent" the safeguards in the Act and create a "parallel and inconsistent" framework without its "careful statutory limitations."
Demetriou said that Ofcom "first decided that it wished to gather large quantities of data ... and then sought to identify statutory functions which could provide an ostensible justification."
TikTok also took issue with Ofcom's statement that it expects to request the information "on a regular basis," and warned that if Ofcom's interpretation of its powers is accepted, the regulator could even ask for this information on a monthly basis. Ofcom, however, said it has set up no recurring regime.
Meanwhile, X, in its witness statement, said that Ofcom's request was "the most burdensome information request X has received from any regulator in any jurisdiction."
Amy Rogers, X's lawyer, said the burden was "extreme" and "disproportionate." The company said that the first set of requests would require at least three to four months of work by "an exclusively dedicated team," while the annual cost of complying with the notices would be "in the millions."
Rogers said that in real-world practical terms, this would require human beings to check hundreds of thousands of data points. A witness for X said that a reduced subset of the data took hundreds of hours to review, and that this work had to take priority over safety and content moderation work.
And while Ofcom was ready with its retort - saying that this was less than a week or two of work per person, and that X was a "very well-resourced" and "extensively regulated entity" - X said that this was not the point, and that Ofcom "can't tell you what the likely cost of this exercise is: it doesn't know."
Javan Herberg, Ofcom's lawyer, said that the regulator "needs to obtain evidence to inform fairly fundamental choices about where to focus its attention."
An Ofcom spokesperson said that "Parliament has charged us with the job of regulating an industry that has been unregulated and unaccountable for more than 20 years."
Meta, TikTok, and X are not challenging the Online Safety Act itself, but how Ofcom has chosen to interpret it. In fact, in September, Ofcom's Oliver Griffiths told UK peers that the regulator was "operating in a highly litigious environment."
Meta, meanwhile, has another case coming up, on October 13 and 14, over how Ofcom's fees are calculated.
What's at stake here is not the removal of harmful content, or censorship, per se, but the paperwork that comes with it. In other words, the platforms are not in court to defend their right to censor, but to defend their right to do so without having to provide detailed reports to Ofcom.
Whatever the court decides, the users who get censored by these companies never had a seat in that courtroom.
