Ask any Edison aficionado how many patents Edison accumulated over his lifetime, and the answer likely will be 1,093. However, that is the number of the domestic patents he was awarded. When you add in his foreign patents the total jumps to 2,332. His foreign patents totaled 1,239--more than his domestic patents, and these overseas patents were awarded to him across 34 countries.
Moreover, during his lifetime, Edison filed roughly 500 patent applications that were rendered unsuccessful or abandoned. This is not unusual at all in the patent world. Generally speaking, only about 65% of all U.S. patent applications filed become successfully granted. If we assume that Edison's misfired patent applications were for his domestic patents, then he had a success rate of 69%--pretty much on target.
Edison's patents were either entire systems or components that support such systems. His patent applications were submitted throughout his lifetime; however, a majority of his most successful applications were filed either between 1872-1890 or 1897-1912.
In fact, Edison recorded his work and inventions in 4,000 notebooks, giving us great insight into the man and his creativity. Since Edison is the model for the modern STEM curriculum, students study his invention process [known in classrooms as the "engineering design process"] and keep notebooks to document their inventive work.
Talk to you again soon...
Harry