Under the Copyright Act, the copyright owner is entitled to several remedies. Along with the damages suffered, the writer can obtain attorney's fees and court costs. In some instances, the writer can obtain profits of the infringer and an injunction. However, in order to take advantage of the full remedies under the Copyright Act, the song must be registered with the U.S. Copyright Office. Moreover, it is important to not delay in bringing the infringement suit once the infringement is discovered. Otherwise, the suit might be barred by what is known as the "statute of limitations". The party sued for infringement may raise certain defenses which are exceptions to copyright infringement. For instance, the doctrine of "fair use" allows a work to be copied if there is no "profit" motive (e.g., for education, research, news). Another legitimate defense is that the new work is a parody of the original work.
Although copyright registration is not mandatory under the Copyright Act of 1976, songwriters are encouraged to officially register their works because if an infringement situation arises, it will be easier to recover damages.
Ben McLane Esq