I read, on another forum, that Michael Baigent is suing Dan Brown for using large tracts of his research from "The Holy Blood And The Holy Grail" in the writing of "The DaVinci Code"
I would very much doubt that there is any chance of Baigent being successful but it won't do the sales of his book any harm.

Interestingly, the books in question start from opposing positions, one claiming to be factual, but to many, verging on the fictional, while the other claims to be fiction while using real organisations and historical facts to appear more factual.

C-flat.