Leon is a Presidential Assistant Professor at the School of Creative Media of the City University of Hong Kong. He researches video game and gambling law, particularly the regulation of loot boxes, gacha, and other gambling-like monetisation mechanics in video games that offer random rewards. He is trained in English law and has been Called to the Bar of England and Wales. He uses empirical legal research methods to assess whether companies are complying with various behavioural addiction-related regulatory rules in different countries through fieldwork, and he advises policymakers on how to improve compliance and implement more effective video game and gambling regulation. He is passionate about open science and conducts registered reports when suitable. His award-winning research has received worldwide coverage in over 820 media features by the BBC, The Guardian, etc. His regulatory complaints against companies based on his research results have established key UK advertising and EU consumer law precedents.

Abstract

Missing the target: Young adults were wrongfully targeted by gambling ads on social media despite UK and Dutch regulations

Aims: Gambling advertising may harm young people. Adverts on social media can be set to only be shown to users belonging to specific demographics. One regulatory intervention adopted in the UK and the Netherlands against gambling harm is to prohibit gambling adverts from targeting young adults. We assessed and compared compliance with these rules and measured the reach of gambling ads against various demographics.

Methods: Using the Meta Ad Library, we retrieved data associated with all gambling ads (20,805 UK and 18,012 Dutch) last shown between May 2025 and May 2026 on Meta-owned social media (e.g. Instagram and Facebook) that were published by advertising accounts required to comply with each respective rule. For each ad, we measured its age-targeting range and reach numbers broken down by demographic groups.

Results: Only 68.5% of UK ads complied, significantly lower than 97.3% of Dutch ads. UK gambling ads received at least 2.4 billion annual impressions on Meta-owned services alone, with reach skewing towards males and younger adults, even though these demographics were not specifically targeted by the vast majority of ads.

Conclusions: Compliance with age-based advertising targeting restrictions was poor in the UK. Compliance was better in the Netherlands but still not perfect. When duly implemented, such rules can reduce exposure for certain vulnerable demographics. Social media algorithms are biased towards delivering gambling ads to men and younger users, despite advertisers lacking such specific intentions.