Da Vinci Code

Vatican Museum
Originally uploaded by jfravel.

So I read an article regarding the da vinci code, and how someone solved part of the mystery surrounding the church symbols. they note this revolves around music and it actually is a musical score.
http://www.cnn.com/2007/WORLD/europe/05/01/davinci.feature.reut/index.html?eref=rss_topstories
the finders of the code have copyrighted the song, if what I read is true. My question is how is this possible. They didn't write the music. I understand the amount of work that must have went into solving this was huge, but what is going on here.