We Value Your Privacy ... Now Take Some Cookies: Measuring the GDPR's Impact on Web Privacy

TL;DR

This study analyzes the GDPR's impact on European websites, showing increased privacy policies and cookie notices, but also highlighting ongoing challenges in implementing effective and user-friendly consent mechanisms.

Contribution

It provides a comprehensive empirical analysis of GDPR compliance on popular European websites, revealing changes in privacy policies and cookie notices, and evaluating technical implementation issues.

Findings

84.5% of websites had privacy policies after GDPR

62.1% of websites display cookie consent notices

Consent mechanisms face technical and usability challenges

Abstract

The European Union's General Data Protection Regulation (GDPR) went into effect on May 25, 2018. Its privacy regulations apply to any service and company collecting or processing personal data in Europe. Many companies had to adjust their data handling processes, consent forms, and privacy policies to comply with the GDPR's transparency requirements. We monitored this rare event by analyzing the GDPR's impact on popular websites in all 28 member states of the European Union. For each country, we periodically examined its 500 most popular websites - 6,579 in total - for the presence of and updates to their privacy policy. While many websites already had privacy policies, we find that in some countries up to 15.7 % of websites added new privacy policies by May 25, 2018, resulting in 84.5 % of websites having privacy policies. 72.6 % of websites with existing privacy policies updated them close to the date. Most visibly, 62.1 % of websites in Europe now display cookie consent notices, 16 % more than in January 2018. These notices inform users about a site's cookie use and user tracking practices. We categorized all observed cookie consent notices and evaluated 16 common implementations with respect to their technical realization of cookie consent. Our analysis shows that core web security mechanisms such as the same-origin policy pose problems for the implementation of consent according to GDPR rules, and opting out of third-party cookies requires the third party to cooperate. Overall, we conclude that the GDPR is making the web more transparent, but there is still a lack of both functional and usable mechanisms for users to consent to or deny processing of their personal data on the Internet.