http://www.usnews.com/news/campaign-2008/articles/2008/07/24/10-things-you-didnt-know-about-fred-smith

Frederick W. Smith

5. As an undergraduate at Yale University, Smith wrote a paper for an economics class in which he described a concept for overnight package delivery by air freight—very similar to what his company, FedEx, would later do. An often-repeated legend holds that his professor gave him a C for the paper, but Smith later admitted that he could not actually recall what grade he had received and had just guessed that it was his "usual gentlemanly C."