Legal Question in Entertainment Law in Florida

I'm not sure I understand the question or which party you are. The collaborated songs have joint ownership until one party assigns or licenses their rights. A joint owner can demand a share of the profits or demand the co-owner cease and DESIST from selling the songs until an agreement for compensation is reached. So, yes, "they" can do "this" until there is a contract stating otherwise.

You should have a lawyer negotiate an agreement on your behalf. Seek one who is experienced is copyright and music entertainment law.

No, a co-artist cannot sell jointly created songs without paying royalties to the other artist. If you collaborated with another Artist to create original songs (musical compositions), the copyrights to those songs belong equally to both Artists. Therefore, if one Artist has been signed to a recording contract with a Record Label, and that Record Label sells, distributes, licenses, or publishes those jointly created songs, both Artist are entitled to royalties from sales.

I recommend that you contact an experienced Intellectual Property attorney to resolve this copyright infringement matter on your behalf.

COMMENTS MADE HEREIN ARE NEITHER LEGAL OPINION NOR DO THEY ESTABLISH AN ATTORNEY-CLIENT RELATIONSHIP.