Celebrities in the US often openly declare their support for a party and political candidate. They have argued that using their music may be seen as an endorsement.
Pharrell Williams and Steven Tyler also sent letters to Trump to order him to stop using their music.
Music is licensed by organisations such as the BMI and ASCAP under the US copyright law. In order to play sound recordings at restaurants, hotels, grocery stores and other public venues, a public performance licence is required.