There may be works in The MLC Public Search that The MLC does not pay out digital audio mechanical royalties for. These works are tagged either as non-musical works or as public domain works.
Non-musical works
Non-musical works include works such as nature sounds, spoken word, or comedy. The MLC does not pay royalties for these works.
Public Domain
Public domain works are no longer protected by copyright law, either due to the copyright expiring, the rightsholder placing it in the public domain, or the works themselves pre-dating the existence of copyrights. They are considered "owned" by the public.
You may register a public domain work if it is an original arrangement and you have listed yourself as the arranger. Otherwise, The MLC does not pay royalties on public domain works.
For information on how to register public domain works, please review our article here.