The US Copyright Act provides strong protection for copyright owners. In a copyright infringement suit, an owner is entitled to recover its actual damages and the infringer's profits (to the extent not included in actual damages). Registration of the copyright is a prerequisite to commencement of suit, and if the copyright was registered in a timely manner, ie within 90 days of first publication of the work or prior to commencement of the infringement, the copyright owner may opt to recover statutory damages, and me be awarded attorney's fees. If the original owner delays in registering the work, however, these significant additional remedies may be unavailable. Thus the prudent course is to register your copyright within 90 of its first publication.
Two recent cases serve as useful reminders of the benefits of registering a copyright in a timely manner.