The issue affected the personal information of some players such as names, contact information, date of birth, hashed social security numbers, account identifiers and information related to BetMGM transactions. The information compromised varied patron to patron.
BetMGM said it promptly launched an investigation after learning of the matter, working with security experts to determine the nature and scope of the issue.
The operator adds it became aware of the matter on 28 November 2022 and believes the breach happened as far back as May 2022.
Despite the breach, BetMGM has no evidence that patron passwords or account funds were accessed in connection with this issue and its online operations were not compromised.
BetMGM CEO Adam Greenblatt said: "We are taking this matter very seriously and are working quickly to investigate it. The security of our platform and our patrons' data is a top priority for BetMGM. We regret any inconvenience this may cause.”
The operator has warned its patrons to remain alert for suspicious activity or unsolicited communications regarding their personal information. It has also arranged to offer credit monitoring and identity restoration services to its affected players at no cost for two years.
Earlier this week, BetMGM became the sports betting partner of the NHL team Nashville Predators.
The multi-year partnership includes branded signage from the operator throughout Bridgestone Arena, the club’s stadium, as well as plans to open an MGM-branded restaurant and bar on the arena’s suite level.