Widespread illegal video game advertising in the UK and South Korea: Many adverts not disclosing loot box presence found using Meta's ad repository.

Background and Aims: Gambling advertising on social media negatively affects public health. Advertising repositories represent a novel data access method for studying the commercial and legal determinants of health. Loot boxes are gambling-like products in video games that players, including young children, buy to obtain random rewards. Their advertising is specifically regulated in the UK and South Korea: loot box presence must be disclosed in any advertising. This rule is enforced differently: the UK relies on industry self-regulation with little deterrence effect, whilst South Korea imposes strict penalties. We assessed and compared compliance to inform policymaking. Methods: Using Meta's advertising repository, we searched whether 394 popular mobile, console, and PC games with loot boxes advertised in the UK and South Korea. The most recently published ads after the rules came into force (N = 2,358) were analysed for compliance. Results: Only 8.4% of UK and 7.6% of South Korean ads disclosed loot box presence. Further, 71.4% of UK disclosures and 44.9% of Korean disclosures were not reasonably visually prominent as required, thus the true compliance rates were 2.4% and 4.2%. Conclusions: Most video games are not complying with international loot box advertising rules. More active enforcement, imposing stricter penalties against non-compliance, providing detailed guidance, and educating foreign companies may lead to better compliance. Governments should not rely on toothless industry self-regulation or unenforced laws to address public health concerns when the evidence indicates widespread non-compliance. Policymakers should adopt laws requiring companies to provide data access to facilitate better independent research.