The latest case has been taken in the name of Musk himself, as he tries to stop an investigation into how X deals with appeals from the public about content moderation decisions.
Last month, Coimisiún na Meán announced that its investigations team had launched an inquiry into whether X has breached Article 20 of the Digital Services Act ( DSA). It will be checking whether people are able to appeal X’s decisions not to remove content.
The regulator, which said the European Commission is co-operating in the investigation, can apply a fine of up to 6pc of the turnover of a company found to be in breach of the DSA.
Musk and his parent company X Holding Corporation, represented by A&L Goodbody, have applied to the High Court to have the investigation stopped.
A second set of proceedings has been lodged on behalf of X Internet Unlimited Company, an Irish entity. It is represented by Fenecas Law, which has now applied for a total of three judicial reviews against the media regulator on the Irish company’s behalf.
The legal firm is also representing X in proceedings against the Appeals Centre Europe, an independent body that deals with appeals made by the public about content-moderation decisions that are made by online platforms such as X.
The five cases taken by X, from a total of nine judicial reviews taken against Coimisiún na Meán since it was set up, represent one front in a transatlantic battle between Big Tech and European regulators.
This has flared up again following the EU’s decision last week to fine X a total of €120m due to breaches of digital rules. The charges against X included that it uses a “deceptive” design in its paid-for blue verification mark.
On Monday, US president Donald Trump described the fine as “a nasty one” and said he did not understand how EU regulators could justify it. “Europe has to be very careful,” he said. “Europe is going in some bad directions.”
Other senior US officials, including secretary of state Marco Rubio, said it represented an attack on US companies in Europe. The European commissioner Henna Virkkunen insisted the fine was proportionate, and said the DSA “has nothing to do with censorship”.
Musk has made extensive use of his own platform to criticise the fine directly, and to repost criticisms by others, including one that said “Elon Musk is not the enemy of Europe. The European Union is the enemy of Europe.”
Central to the case he has launched against Coimisiún na Meán is whether X Holding Corporation can legally be held to be the “provider of the X online platform”.
His lawyers have told the High Court that Musk takes issue with this proposition.
They have pointed out that when X was designated as a Very Large Online Platform (Vlop) under European digital law, it was the Irish entity that was informed. Therefore, American-based companies could not now be drawn into an investigation.
Lawyers representing Coimisiún na Meán have told the High Court the regulator is concerned that an attempt is being made to stop its work.
Justice Mary Rose Gearty agreed to a temporary stay in both proceedings until January 23 next.
This article was amended on Tuesday, December 9 at 8.40pm to correct the number of judicial reviews being launched by X
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