News Release

Microtransactions can move popular online games closer to online gambling

Peer-Reviewed Publication

Society for the Study of Addiction

Many popular online games include the option of paying small fees (microtransactions) to access additional features or content that enhance the player's experience. An editorial published today by Addiction argues that some online games use in-game purchasing systems that disguise or withhold the long-term cost of microtransactions until the player is already financially and psychologically committed. Such purchasing systems push free-to-play online gaming closer to gambling and may present financial risks for vulnerable players.

The authors focus on a monetization scheme called the 'loot box', an in-game reward system in which players can repetitively buy a random selection of virtual items. Players hoping to win a particular item may end up repeatedly buying loot boxes at significant personal expense. The authors argue that because loot boxes require no player skill and have a randomly determined outcome or prize, they function similarly to gambling slot machines.

The authors call loot boxes and similar schemes 'predatory monetization' because they encourage repeated spending using tactics that may involve limited disclosure of the product, unavoidable solicitations, and manipulation of reward outcomes to encourage purchasing behaviours over skilful play. The authors point out that some of the top-earning game publishers have registered patents for microtransaction systems that incentivise the player to spend money (1,2) but there are few regulations or consumer protections associated with these systems.

The editorial appears in the wake of the World Health Organization's announcement on 18 June that it plans for the first time to include 'gaming disorder' in its diagnostic manual, the International Classification of Diseases.


1. Marr M. D., Kaplan K. S., Lewis N. T. U.S. Patent No. 9,789,406 [internet]. 2017 October 17. Available at: (accessed 12 January 2018).

2. Xue S., Wu M., Kolen J., Aghdaie N., Zaman K. A. Dynamic difficulty adjustment for maximized engagement in digital games [internet]. 5 April 2017. Available at: (accessed 12 January 2018).

For editors:

This paper is free to download from the Wiley Online Library after the embargo has lifted, or by contacting Jean O'Reilly, Editorial Manager, Addiction,, tel +44 (0)20 7848 0853.

Interviews with lead author Dr Daniel King: contact him at the University of Adelaide (Australia) by email or telephone (+61 883133740).

Full citation for editorial: King DL and PH Delfabbro (2018) Predatory monetization schemes in video games (e.g., 'loot boxes') and Internet gaming disorder. Addiction 110: doi: 10.1111/add.14286.

Addiction is a monthly international scientific journal publishing peer-reviewed research reports on alcohol, illicit drugs, tobacco, and gambling as well as editorials and other debate pieces. Owned by the Society for the Study of Addiction, it has been in continuous publication since 1884. Addiction is the number one journal in the 2016 ISI Journal Citation Reports ranking in the substance abuse category for both science and social science editions.

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