John Douglas Arnold (born 1974) is an American philanthropist, former Enron executive and founder of Arnold Ventures LLC, formerly the Laura and John Arnold Foundation. In 2007, Arnold became the youngest billionaire in the U.S. His firm, Centaurus Advisors, LLC, was a Houston-based hedge fund specializing in trading energy products that closed in 2012. He now focuses on philanthropy through Arnold Ventures LLC. Arnold is a board member of Breakthrough Energy Ventures. Early life Arnold was raised in Dallas, Texas, and he was the younger of two sons. His mother later would work as an accountant at Centaurus. His father was a lawyer and died when Arnold was 18. At 14, he started his first company selling collectible sports cards called Blue Chip Cards. A 1995 graduate of Vanderbilt University, he completed a degree in mathematics and economics in three years. He is a member of Lambda Chi Alpha. Career After college, he began his career at Enron as an oil analyst, but soon was promoted to assistant trader. In 1996, a year after starting at Enron, he moved to oversee the trading of natural gas derivatives at the Natural Gas Desk upon the departure of Jeff Bussan. Using their new Internet-based trading network, EnronOnline, he is credited with making three quarters of a billion dollars for Enron in 2001 and was rewarded with the largest bonus in Enron history, some $8 million. His former colleagues dubbed him "king of natural gas." When Enron collapsed, he was not accused of any wrongdoing. He then founded Centaurus, a hedge fund, with his previous year's bonus in 2002. He was widely quoted for his viewpoints on the industry by a government commission. During the collapse of Amaranth Advisors, Centaurus is widely credited as being one of the major players on the other side of their position, returning as much as 150% in 2005. August 2008, Centaurus acquired around 10% of the shares of National Coal Corporation (NCOC). In 2009, Arnold gave a public speech to the U.S. Commodity Futures Trading Commission (CFTC), in which he opposed limits on financially settled trading positions but supported limits in the physical energy futures as they near expiration. Arnold announced his retirement from running the hedge fund on May 2, 2012. Other interests In 2019, Arnold became the chairman of Houston's 2026 bid for the FIFA World Cup. Philanthropy Arnold started donating to the Knowledge Is