Here's a nice article about patenting the atomic bomb

http://www.npr.org/templates/story/story.php?storyId=89127786 

 Some interesting quotes:

 "The idea behind the patent program was to give the government some legal protection ... when the U.S. government exited World War II, they owned patents on practically everything related to atomic energy research at that point ...  By 1947 ...  about 2,100 patent applications [were] approved for filing."

 It is indeed very fortunate for the free world, that the US had owned the patents, and not somebody else...