TikTok Technology Limited v DPC - 5 May 2026

• Judgment Date: 05 May 2026
• Year: 2026
• Issuer: Supreme Court

1

AN CHÚIRT UACHTARACH

THE SUPREME COURT

S:AP:IE:2025:000148

[2026] IESC 27

O’Donnell C.J.

O’Malley J.

Hogan J.

Murray J.

Collins J.

IN THE MATTER OF SECTIONS 142 AND 150 OF THE

DATA PROTECTION ACT 2018

BETWEEN/

TIKTOK TECHNOLOGY LIMITED AND TIKTOK INFORMATION

TECHNOLOGIES UK LIMITED

APPLICANTS/

RESPONDENTS

AND

DATA PROTECTION COMMISSION

RESPONDENT/

APPELLANT

JUDGMENT of Mr. Justice Gerard Hogan delivered on the 30th day of April 2026

2

Background

1. The concept of national procedural autonomy is a fundamental principle of European

Union law. It reflects the very practical reality that not only is the Union composed of

different types of legal families, but also that each of the Member States have their own

legal systems and their own very different procedures. This national procedural

autonomy is, of course, tempered by the concepts of equivalence and effectiveness

which the Court of Justice has developed over the years: see, e.g., Lenaerts, Gutman,

Nowak eds., EU Procedural Law (Oxford, 2023) at pp. 122-124. There may, of course,

be special cases where, exceptionally, Union law reaches into national procedural law

and specifies that a particular remedy must be made available. These cases are,

however, exceptional and, reflecting this fact, where the Union legislature so acts, it

does so in express terms.

2. Over and above all of this, the concept reflects an even more profound principle,

namely, the division of juridical sovereignty as between the Union and its Member

States. Just as the Member States must uphold the supremacy of Union law within its

proper sphere of application by virtue of their duty of loyal co-operation under Article

4(3) TEU, so too must the Union respect the autonomy of the Member States. After all,

as the German Constitutional Court observed in its landmark decision of 12th October

1993 in the Maastricht Treaty case (89 Bverf GE 150 at 190), it is the Member States

who are the masters of the Treaties (“Herren der Verträge”) and not the other way

around. The Union does not, therefore, have its own autochthonous sovereignty. It

instead rather enjoys only that with which it has been conferred by the Member States.

Subject to the exceptions I have mentioned, national procedural autonomy remains the

preserve of the Member States. It has never been transferred to the Union.