Are all Youtube views monetized? Follow
In general, different rules or "norms" can be assigned to the parts of a video to be claimed (visual part, music part, lyrics part, etc.). Soundreef assigns the rule "MONETIZATION" to the songs for which it claims on Youtube the shares of music ownership rights on behalf of its subscribers.
However, if there are several people claiming a part of the video in the same territory, YouTube will apply the most restrictive rule indicated between the parties.
Here you can find detailed explanation about Youtube list of norms and how they work in different cases.