The U.S. Department of Justice filed an application Thursday to intervene in support of Elon Musk's X in its effort to overturn a €120 million fine levied by the European Commission.

The fine, issued in December 2025, marked the first penalty under the EU's Digital Services Act. Regulators cited deceptive design in X's paid blue checkmark system, insufficient transparency in advertising, and failure to provide researchers access to data.

Assistant Attorney General Brett Shumate stated that the European Commission had inappropriately sought to extend its regulatory reach to American companies operating outside its jurisdiction. He added that the U.S. would not tolerate regulatory overreach aimed at controlling American innovation and economic growth.

The intervention comes under the Trump administration, which has criticized the DSA as an example of extraterritorial enforcement that could harm U.S. tech firms. The DOJ noted concerns over the commission's approach to attributing liability, which it said could affect other American digital services.

X, headquartered in the U.S. with its EU base in Ireland, filed its own appeal earlier this year. The company has argued the fine violated due process and targeted individuals and entities beyond the platform itself.

The European Commission responded Friday by affirming its intent to defend the penalty in court. A spokesperson described the bloc's right to enact laws protecting its citizens as sovereign.

The case highlights ongoing tensions between U.S. authorities and EU regulators over tech oversight. The fine stems from a two-year investigation into X's compliance with rules on content moderation and platform transparency.

If upheld, the decision could set precedents for how the EU applies its digital rules to foreign companies. The DOJ emphasized the importance of consistent application of territorial jurisdiction principles under international law.