Unless you have explicit permission from all concerned parties, it is not possible to register songs with uncleared samples.
Example: you write a song containing a Michael Jackson sample and you don't have clearance from Jackson's label or publisher to use this sample. It's thus not possible to register your song for the collection of songwriting or publishing royalties.
We highly recommend checking this database before you attempt to get permission for samples. Dontsample.me provides the most comprehensive list of current artists that will not approve any samples of their works.