Apparently Marvin Gaye is suing Robin Thicke for Blurred Lines because it sounds very similar to Got to Give it Up. Robin Thicke apparently lost in the first round today. Don't know how this will play out. One of the previous lawsuits I can think of like think was Vanilla Ice and The Beatles and Vanilla Ice won.
Here's a link for the article.
And here is a comparison of both songs.