The logos of the manufacturers of clothing worn by Olympians are permitted .
The IOC Charter specifies that such logos must not be marked conspicuously for advertising purposes , and imposes restrictions on their size , frequency , location and appearance .
The logos of the manufacturers of clothing worn by Olympians are permitted , but the IOC Charter specifies that such logos must not be marked conspicuously for advertising purposes , and imposes restrictions on their size , frequency , location and appearance .