A complaint has been filed against TikTok by a Vienna-based privacy group, alleging that it secretly monitors activities of other groups through third-party trackers.
The complaint also included two other applications named Grindr and AppsFlyer, alleging violations of European Union privacy laws.
As reported by Reuters, a data privacy group, None of Your Business NOYB claimed that the companies tracked user activities across different apps without consent, potentially exposing sensitive data.
The group said TikTok monitored a user’s Grindr activity using data from AppsFlyer, raising concerns about compliance with the General Data Protection Regulation GDPR.
The Austrian organization NOYB alleged that TikTok used this information for targeted ads and analytics and did not inform the user until after repeated requests.
While according to NYOB, TikTok responded that the tracked data was only used for reasons including "personalized advertising, analytics, and security."
The group also said neither AppsFlyer nor Grindr had legal grounds to share the data with TikTok.
NOYB further explained that TikTok and Grindr (dating app) illegally shared users’ sensitive information, while AppsFlyer facilitated those unauthorized data transfers without consent.
The complaints were filed to Austria's data protection authority on Wednesday, December 17, 2025, and urged Austrian regulators to impose fines and compel the companies to cease such practices.