As a composer, you have two sets of rights: the writer's share and the publisher's share. The writer's share is attributed to you as the songwriter or composer. In contrast, the publisher's share refers to the revenue for which admin rights can be attributed to a music publishing administrator such as UniteSync.
As the owner of both the writer and the publisher shares, you can transfer your rights in the publisher's share to a publishing deal. When you do this, the composition's publisher is authorized to issue licenses and collect royalties for the works subject to the deal. If you enter into a Publishing Administration agreement instead, you are not transferring ownership but simply the right to administer the songs.
By attributing the publisher's share to a publishing administrator, you can maximize the potential royalties for the writer's share by ensuring a more complete and efficient royalty collection process globally. This is done via directly registering songs with your local PRO and thousands of other income sources worldwide.
For example, let's take the song "Bad Guy" performed by Billie Eilish. Billie and her brother Finneas O'Connell co-wrote this song. Finneas has entered into an administration agreement with Kobalt. Because of this, Kobalt is responsible for registering his works with his local PRO, ASCAP, and many other income sources worldwide. Kobalt is responsible for collecting the publisher's share from ASCAP and thousands of other income sources globally, while the writer's share continues to be paid directly to Finneas by ASCAP.
By handing over the administration of his songs, Finneas can focus on writing music instead of worrying about registering his songs and collecting the money they generate.