What type of content do I need in order to be represented by Music Services to make claims on my behalf in YouTube’s Content ID system?

In order for Music Services to represent you, you will need to have the following:

ownership of sound recordings and/or the musical works embodied in those sound recordings;
the ability to authorize Music Services, exclusively, to license digital service providers within the territory for which Music Services represents you and collect royalties from those providers for uses of the sound recordings or musical works you own; and
audio files of your sound recordings that are sufficiently distinct so that it can act as a reference file when videos are scanned by YouTube’s Content ID programs in an attempt to identify videos containing the sound recordings or musical works you own.

The sound recordings or musical works you register with Music Services cannot be or contain:

unlicensed samples, sound effects, sound bites, beats, or royalty-free music;
audio made available for free from sources such as Garage Band, Ableton, Logic, Fruity Loops;
content licensed non-exclusively from a third party;
content released under Creative Commons or similar free/open licenses; or
public domain sound recordings.

More information about YouTube’s requirements can be found at: https://support.google.com/youtube/answer/2605065?hl=en