Report reveals prevalence of rogue website advertising
June 26, 2026

By Colin Mann



Internet websites and mobile apps that provide access to content, goods or services infringing intellectual property rights (IPR) on a commercial scale often use the sale of advertising space as a key source of revenue.

In addition to generating income for IPR infringers, the presence of legitimate brand advertising on such platforms can mislead consumers into believing they are accessing legal content, goods or services. To address this issue, the European Commission sponsored a Memorandum of Understanding (MoU) on online advertising and IPR. The European Union Intellectual Property Office (EUIPO) commissioned White Bullet to carry out the 2025 Ad Monitoring Exercise to assess the impact of the MoU on IPR-infringing websites and apps, estimate ad volumes and revenues, and compare results with previous analyses from 2024, 2023 (Q4), 2021, 2020 and 2019.


Main findings

• 5,671 websites and 337 mobile applications across 18 EU Member States, as well as the United Kingdom (UK) and United States (US) as control countries, were analysed. Of these, 37 per cent of websites and 57 per cent of apps were classified as illegal, while the remainder were classified as high-risk (verified as infringing but have not (yet) been adjudicated by national authorities).

• The monitored websites generated 12.7 billion ad impressions and the monitored apps 3.4 billion. Most website impressions originated from high-risk sources (58 per cent), while illegal apps accounted for the majority of app impressions (52 per cent). Website ad impressions declined by 20 per cent between Q1 and Q4, indicating changes in traffic and advertising patterns across infringing services.

• Branded advertising accounted for 66 per cent of ad impressions on monitored websites and 96 per cent on monitored apps. Major brand advertising represented 36 per cent of website impressions and 16 per cent of app impressions, increasing substantially compared with 2024. Retail, gambling and media were the dominant sectors on websites, while media overwhelmingly dominated advertising on apps.

• A total of 61, 628 advertisers were identified on monitored websites and 7,088 on monitored apps. Major brands represented 8 per cent of website advertisers and 10 per cent of app advertisers, demonstrating the continued exposure of reputable brands within infringing environments.

• Total estimated revenues reached €382 million worldwide for monitored websites and €15 million for monitored apps. Within the 18 monitored EU countries, websites alone generated an estimated €28.5 million in advertising revenue.

The continued monetisation of infringing content through legitimate advertising highlights persistent weaknesses in the digital advertising ecosystem. The findings suggest that Infringing Watch Lists (IWLs) may have become less effective in limiting the placement of advertising on infringing websites.

Fraud and malware advertising increased significantly on monitored websites, rising from 14 per cent of ad impressions in 2024 to 25 per cent in 2025. This underlines the growing risks faced by both consumers and advertisers when engaging with infringing online services.