The Comrades Marathon Association has warned that illegal advertisers will be prosecuted if they elbow their way into this year's race.
The association's general manager, Gary Boshoff, said it would not tolerate "ambush marketing" by advertisers who attempt to use the race for advertising.
Over the years, ambush marketers have used a variety of means to circumvent the regulations on the use of the event as a marketing platform.
The usual strategy is to erect banners or other advertising material on the route.
This year's race takes place on Sunday June 17. - Canaan Mdletshe