---
title: "Case C-25/17: judgment of 10 July 2018"
canonical: "https://dposchool.com/gdpr/case/c-25-17"
source: "https://curia.europa.eu/juris/liste.jsf?num=C-25/17&language=en"
source_note: "Only the judgment as published by the Court of Justice is authoritative."
text_as_of: "2026-10-28"
last_reviewed: "2026-10-29"
language: "en"
publisher: "DPO School"
---

Court of Justice judgment · Case C-25/17

# Proceedings brought by Tietosuojavaltuutettu

[Reviewed by Sergio Maldonado Elvira on 29 October 2026](https://dposchool.com/gdpr/about#review)

- **Case:** C-25/17
- **Court:** Court of Justice
- **Date of judgment:** 10 July 2018
- **ECLI:** ECLI:EU:C:2018:551
- **Instrument:** Directive 95/46/EC (pre-GDPR; reasoning still applied under the GDPR)
- **Provisions:** [Article 2(2)(c)](https://dposchool.com/gdpr/article/2#2-c), [Article 4(6)](https://dposchool.com/gdpr/article/4#4-6), [Article 4(7)](https://dposchool.com/gdpr/article/4#4-7), [Article 26](https://dposchool.com/gdpr/article/26)

Listed under "Related (earlier law or other instruments)": this judgment concerns earlier law or another instrument, not the GDPR alone.

## Holding (summary, not the official text)

Notes taken by members of a religious community during door-to-door preaching are not a purely personal activity and can form a filing system; the community can be a controller jointly with its members even without access to the data.

## Official source

- [Case C-25/17 on CURIA](https://curia.europa.eu/juris/liste.jsf?num=C-25/17&language=en)
- [Judgment on EUR-Lex (CELEX 62017CJ0025)](https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:62017CJ0025)

Checked against the official source on 28 October 2026.

Only the judgment as published by the Court of Justice is authoritative. This is reference material, not legal advice.

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