Overlord complete

Unless it states that in the store page.
Example:
Already own Left 4 Dead? You can give your extra copy to a friend when you purchase this Bundle.

Not true, but there are few that do, most of them being Valve titles. An example being Half-Life 2 and Episode 1 will have inventory versions added if you own them while activating The Orange Box.

As the guy said up. Most of the times, almost always, you don't get an extra copy. But there have been cases where you do. It usually states it on the deal page, or rarely not and users report it being like this.