John D. Rockefeller (July 8, 1839 – May 23, 1937) was an American businessman and philanthropist best known for building the Standard Oil Company into the first great business trust, revolutionizing the petroleum industry, achieving a monopolistic market share of 90%, and becoming America’s first billionaire in the process.  He was a diligent and creative operator, finding ways to defeat or acquire his competition to dominate the business of refining petroleum, and then pioneering the concept of vertical integration, whereby Standard Oil was directly involved in every step in the process, from drilling to refining to distributing the finished products to the end user.  He believed that the efficiencies achieved by minimizing competition would benefit customers with lower prices and greater product availability. As the largest and wealthiest trust, Standard Oil was a natural target of the trustbusters, who eventually succeeding in anti-trust litigation. Rockefeller’s was characteristically sanguine – “buy Standard Oil”.   He retired from Standard Oil in 1897 and proceeded to give away a significant portion of his wealth, designing the philanthropic foundation as a means to systematically donate. His focus was on medicine, education, and science, and Rockefeller gifts helped found the University of Chicago and Rockefeller University.   When he died at the age of 97 in 1937 his net worth was equal to $336 billion in inflation-adjusted dollars, equal to 1.5% of the U.S. GDP.