In a meeting with professional Dota 2 teams competing in Valve's The International 2018 competition, the company told the teams they should not accept any future sponsorships from gambling websites. Multiple existing contracts would be discussed at a later date.
VPEsports reports that several of the teams already have existing contracts, and no clear instructions were given for ending them. When the issue was brought up by a team manager, the Valve representative said the issue would be discussed another time.
This is by no means an unprecedented move. In 2015, Valve banned seven players from all future Valve-sponsored events after an incident involving CS:GO match fixing. The company reiterated its anti-gambling policy, which states that "Professional players, their managers, and teams' organization staff, should under no circumstances gamble on CS:GO matches, associate with high volume CS:GO gamblers, or deliver information to others that might influence their CS:GO bets."
As a follow-up to that, Valve cautioned players in the ESEA League that allowing gambling sites to sponsor semi-professional or professional teams was "a direct conflict of interest with the League and the guidelines set forth by Valve." At the time, the company advised that if a sponsorship existed, it could not be visibly promoted, such as with a team name.
Other hosts and organizers of major esports events, such as Riot Games, have taken similar approaches. In one example reported by Dotesports, Swedish team Ninjas in Pyjamas was forced to end a sponorship agreement with Betway per the League of Legends Championship Series rules after the team included its logo on jerseys worn by several of its teams, though none that participated in that specific tournament.
GamesIndustry.biz has reached out to Valve for comment.