Was Thomas Edison the world's first patent troll, or at least the most famous? Fortune's Business Innovation Insider displays a list of the "nine things Edison never actually invented." In case you were wondering, yes, Edison did sue rivals to enforce his patents.
Just for fun, compare the lives of Edison and his great rival Nikola Tesla. Edison was everything that Tesla was not. In particular, financially successful. However Tesla really was a great inventor. Without Tesla's polyphase alternating current power distribution technology, the world would not have developed the widespread use of electric power.
Which is not to say that Edison did not contribute anything...but his contributions were more developmental than inventive in nature.