Alerts sent to partners, including a number of major sports governing bodies, were in relation to 126 matches over the past 12 months.
These alerts mainly concerned football, with 110 sent out, including 44 to Fifa and 38 to Uefa, football’s global and European governing bodies, respectively.
Seven alerts were sent to the International Olympic Committee, with the other 73 split between the Esports Integrity Coalition (ESIC), the Swiss Lottery and Betting Board, the Tennis Integrity Unit and other partners.
A total of 1,113 alerts were generated in 2020, the majority of which (936) were created before the start of an event. Some 27 alerts were generated based on in-play odds changes, and a further 150 after the end of an event.
The GLMS classifies its alerts as red, yellow and green, depending on the seriousness of the incident.
The majority (715) were green cases, which related to issues such as team news, member information, a wrong starting price or minor odds changes. Some 217 were yellow alerts for incidences including unexplained odds changes, rumours of match-fixing and member information.
Red-level alerts, including suspicious odds changes, rumours of match-fixing from a named source and Betfair exchange volume and patterns, made up 86 alerts, up from 50 in 2019. A further 95 alerts in 2020 were not categorised.
Football remained the sport of highest concern to the GLMS, with the 832 alerts sent accounting for almost three quarters of all alerts for 2020.
Basketball ranked second in terms of suspicious betting with 134 reports, then ice hockey on 55, tennis with 50, 11 for American football and 10 each for esports and volleyball.
Five alerts were registered for handball betting, three for baseball and one each for table tennis, badminton and sepak takraw. The GLMS did not file a single report for hockey, rugby, cycling or boxing in 2020.
In terms of geographical performance, Europe was by far the continent of most concern, with 727 alerts during the year. Football led the way on 559 reports, ahead of basketball on 70 and tennis with 29.
Asia saw a total of 191 alerts, the vast majority of which were related to football, while South America had 90 alerts, North America 64, Africa 23 and Oceania just seven. A further 11 alerts were classed as international by the GLMS.
The main reason for the alerts that were flagged in 2020 was team-related news, with this accounting for 402 of cases during the year.
Some 192 alerts were raised in relation to significant odds changes, 140 for the wrong opening price, 114 when odds changes required more investigation, and 83 following a specific request.