There are a variety of classifications. For example, there are people who have a similar name or same name and a similar or same birth date. I'm thinking, for example, of someone with the last name Mohammed born January 1, 1985. People from some regions in the world don't have the same birth certificate documentation, and they will arbitrarily select a birth date that will be recorded in government systems. This necessarily means the system will generate a red flag for those kinds of files.
On November 20th, 2012. See this statement in context.