ICCL Launches Class Action Against Microsoft Over 'Real-Time Bidding' Data Breach
On May 26, 2025, the Irish Council for Civil Liberties (ICCL) filed a class action lawsuit against Microsoft in the Irish High Court. The lawsuit alleges a 'very large' data breach within Microsoft's Real-Time Bidding (RTB) advertising system, claiming that it broadcasts sensitive personal data, exposing users to malicious profiling and undermining European security. The action aims to force Microsoft to comply with the EU's General Data Protection Regulation (GDPR).
Signal context
First seen: May 26, 2025
Last updated: Jun 26, 2026
Status: Public signal
Key points
- Class action lawsuit launched by Irish Council for Civil Liberties (ICCL) on May 26, 2025.
- Targets Microsoft's 'Real-Time Bidding' (RTB) advertising system.
- Alleges a 'very large' data breach and non-compliance with GDPR.
Signal analysis
BetaThis analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.
Sector: Information
Likely country: 🇮🇪 Ireland
inferred from source domains
Watch internet-facing systems, credential abuse and exploit activity.
- Source type: outside the affected organization
Impact area: Confidentiality
Likely asset: User or customer data
- 26 signals in the same sector
- 90 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
Microsoft's vast advertising business is target of ICCL Enforce application for class action launch under EU data law - Irish Council for Civil Libertieshttps://www.iccl.ie/news/iccl-initiates-irelands-first-ever-class-action-lawsuit-targeting-microsofts-european-advertising-system/Public source from iccl.ie.
Irish court approves first class action against Microsoft RTB data breach - PPC Landhttps://ppc.land/irish-court-approves-first-class-action-against-microsoft-rtb-data-breach/Public source from ppc.land.
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