In video games, skin gambling is the use of virtual goods, which are most commonly cosmetic elements such as "skins" which have no direct influence on gameplay, as virtual currency to bet on the outcome of professional matches or on other games of chance. It primarily has occurred within the player community for the game Counter-Strike: Global Offensive by Valve Corporation, but practice of it exists in other game communities. Valve also runs the Steam marketplace which can be interfaced by third-parties to enable trading, buying, and selling of skins from players' Steam inventories for real-world or digital currency, though Valve itself condemns the gambling practices and such activity violates Steam's Terms of Service.
Valve added random skin rewards as part of an update to Counter-Strike: Global Offensive in 2013, believing that players would use these to trade with other players and bolster both the player community and its Steam marketplace. A number of websites were created to bypass monetary restrictions Valve set on the Steam marketplace to aid in high-value trading and allowing users to receive cash value for skins. Some of these sites subsequently added the ability to gamble on the results of professional matches or in games of chance with these skins, which in 2016 was estimated to handle around $5 billion of the virtual goods. These sites, along with Valve and various video game streamers, have come under scrutiny due to ethical and legal questions relating to gambling on sporting matches, underage gambling, undisclosed promotion, and outcome rigging. Evidence of such unethical practices was discovered in June 2016, and led to two formal lawsuits filed against these sites and Valve in the following month. Valve subsequently has taken steps to stop such sites from using Steam's interface for enabling gambling, leading to about half of these sites closing down, while driving more of the skin gambling into an underground economy.