The issue is strictly a procedural one. For example, you get the copyright as soon as you author a work and put it in a tangible form of expression (let's say it is source code for a product you have developed). Then, you go about your business for several years using your copyrighted work internally and making sure it is subject to trade secret protections as well. If, after that time, someone lifts the code illegally and uses it to create a competitive product, you have a claim for copyright infringement, among other things. But you cannot file that claim in federal court unless and until you have registered the copyrighted work as a prerequisite to maintaining the suit. Many U.S. jurisdictions say you cannot even sue at all on the copyright claims until the copyright has finally been registered. In California, the Ninth Circuit holds that you can file the federal suit once you have applied for the copyright registration, even though it is not complete.

Therefore, once you create a qualifying work, you have a fully perfected copyright immediately. You just can't sue on that interest for infringement until you have taken the additional step of registering the copyright. You can, however, register at any time prior to filing an infringement action, even if that is many years after the copyright was created. For enforcement purposes, then, it is basically a 2-step process.

Oracle's problem is that it is at the tail end of a trial and has no ability at this point to do anything about registration. If Google is right concerning the motion, Oracle will be out of options on its copyright claims.