Benjamin Franklin was a giant among the founding fathers of the United States. He was also an inventor and scientist, one of few Americans who was a member of the British Royal Society.
Among other things, Franklin invented his famous Franklin Stove and the lightning rod. The latter, of course, has saved countless thousands of lives.
Franklin, who became the richest man in America, did not patent any of his inventions. According to Wikipedia, he believed "that as we enjoy great advantages from the inventions of others, we should be glad of an opportunity to serve others by any invention of ours, and this we should do freely and generously."
Patent the square shape of a tablet? Phew!