Remember that you do not need permission if you are using something that is not copyrightable or is in the public domain. You also don't need permission if you are using it in a way that does not implicate one of the rights of copyright holders or is permitted by a user’s right, such as fair use. For more information on these topics, please consult Copyright Basics.
There are two ways that copyright protects music.
Musical works: A musical work is the composition itself, possibly including lyrics. Musical works receive the full set of rights under copyright law, just like like literary, dramatic, and choreographic works, pantomimes, and motion pictures and other audiovisual works.
Sound recordings: A sound recording is a fixation of a series of sounds that does not accompany an audiovisual work. For example, Fleetwood Mac's 1975 rendition of Landslide is a sound recording. Their 1980 live concert recording of it is also a sound recording and is a separate copyrighted work. The Dixie Chicks' 2002 cover of the song is yet another copyrighted work. Copyright in sound recordings is slightly narrower than copyright in other works—it includes a right to perform the work to the public, but only "by means of a digital audio transmission." Performing a sound recording to the public in an analog manner does not implicate the copyright in the sound recording. Before 1972, sound recordings were not eligible for federal copyright protection in the United States. For more information about pre-1972 sound recordings, we recommend Protection for Pre-1972 Sound Recordings under State Law and Its Impact on Use by Nonprofit Institutions: A 10-State Analysis (PDF), a report prepared for the National Recording Preservation Board by the Program on Information Justice and Intellectual Property in 2009.
When a sound recording is based on a musical work, many uses of the sound recording are also uses of the musical work. In those cases, if permission is needed, it must be obtained from the rightsholder of each work.
In the United States, public performance licenses for musical works are generally obtained from one of the following performance rights organizations (“PROs”). All three of these PROs sell blanket licenses, which permit licensees to perform publicly any music from the licensor’s catalog. Licenses from these organizations are for “small rights” only. Separate licenses involving “grand rights” must be obtained for dramatic performances of musical works.
By custom, in the US music industry, the music publisher directly licenses the musical work for dramatic performances (see below), for reproduction by sheet music publishers, and for publication by foreign publishers. It also directly licenses synchronization rights, the rights to use the musical work as part of an audiovisual work such as a movie, TV show, or TV commercial. Several of the largest music publishers are listed below.
To license a public dramatic performance of a musical work, you need a license that covers “grand rights.” This is a contractual distinction not included in copyright law itself. Grand rights are involved in:
Performances of musical works that tell a story (e.g., operas, musicals) UNLESS only an excerpt is used, and in a non-storytelling way, AND
Performances that combine musical works with choreography, acting, etc.
Grand rights: Vocalists performing a scene from an opera, an actor singing a pop song during a play
Small rights: A soloist performing an aria
Grand rights can usually be obtained from the music publisher, or even the composer.
Mechanical licenses apply to reproduction and distribution of musical works on records and CDs, in permanent digital downloads, and in some other digital uses. For example, these licenses permit subsequent recording artists to “cover” songs written by others. The royalty rates for records, CDs, and permanent digital downloads are set by statute, and the licenses are compulsory. The Harry Fox Agency is the primary source for mechanical licenses in the United States.
The copyrights in sound recordings are customarily held by record companies. If a recording was self-released, the artist most likely holds copyright. Amazon also lists the copyright holder for most of the music it sells and can be a good resource for finding this information. The three largest record companies are listed below.
Because there is no analog public performance right in sound recordings, terrestrial radio and television stations and venues such as bars and restaurants do not need licenses to perform sound recordings publicly. (They do, however, often need licenses for public performances of the underlying musical works, as explained above.)
There is a digital public performance right for sound recordings. Sound Exchange is the primary performance rights organization licensing the right to perform sound recording to the public by means of a digital audio transmission. It issues licenses to commercial webcasters, noncommercial webcasters, and other services such as satellite radio. The licensing rates it charges are set by the Copyright Royalty Board.
YouTube's Content ID system allows rightsholders to give YouTube examples of their copyrighted works. Then, Content ID searches all of the videos on YouTube, looking for content that matches the copyrighted works. Participating copyright holders can set policies for how YouTube treats content that matches their work. For instance, the copyright holder can monetize a video that matches its content, it can mute its content in the video, or it can block the video, either worldwide or only in some countries.
YouTube's Music Policies page lists the current policies for Content ID participants. Those policies are subject to change at any time. A match that results in monetization this month could result in blocking next month. Furthermore, using music from the Music Policies page will still result in a Content ID claim. For more information on YouTube's policies, visit their materials on Copyright and rights management.
YouTube's Audio Library contains music that is free to use on YouTube and will not result in Content ID claims. In many cases, these tracks have been licensed under one of the Creative Commons licenses or dedicated to the public domain.