John Mars

John Mars (John F. Mars) is the son of Forrest E. Mars Sr. and a grandson of Frank C. Mars, who founded Mars when he began making and selling butter cream candy from his kitchen in Tacoma, Washington, in 1911.⁠[1][2]

He graduated from The Hotchkiss School in 1953 and later earned a bachelor’s degree from Yale UniversityYale UniversityYale University is a research university in New Haven, Connecticut. Its predecessor, the Collegiate School, received a charter in 1701. Trustees chose New Haven in 1716; the institution became Yale College in 1718 and Yale University in 1887. Yale provides undergraduate, graduate and professional education and has 14 undergraduate residential colleges. As of October 2026, its president was Maurie McInnis, who took office in July 2024. In 2026, Yale expanded aid for incoming undergraduates and celebrated its 325th anniversary.Open the full entry.⁠[3][1]

Forrest E. Mars Sr. died in Miami in 1999 at age 96, and John Mars, his sister Jacqueline MarsJacqueline MarsJacqueline Mars (Jacqueline Badger Mars) is an American businesswoman and philanthropist, a granddaughter of Mars founder Frank C. Mars, and the owner of an estimated one-third of the family-owned candy, food and pet care company.Open the full entry and his brother Forrest Mars Jr. inherited stakes in Mars.⁠[2][1]

Forrest Jr. died on July 26, 2016, at age 84. ForbesForbesForbes is an American business media brand that began with Forbes magazine, founded by B.C. Forbes in 1917. It is known for rankings such as the Forbes 400, the World’s Billionaires list and 30 Under 30, and operates Forbes.com, ForbesLive events and licensed editions in 81 countries. Since 2014 a majority stake has been held by the Hong Kong investment group Integrated Whale Media; a 2021 plan to list on the New York Stock Exchange through a special purpose acquisition company was terminated in 2022. It is headquartered in Jersey City, New Jersey.Open the full entry estimates that John Mars and Jacqueline Mars each own about one-third of Mars, with Forrest Jr.’s four daughters believed to own the rest.⁠[3][1]

On April 8, 2019, the Smithsonian Board of Regents voted to recognize the generosity of John and Adrienne Mars to the SmithsonianSmithsonian InstitutionThe Smithsonian Institution is a museum, education and research institution created by the U.S. Congress in 1846 with the bequest of the English scientist James Smithson. Based in Washington, D.C., it runs museums such as the National Air and Space Museum and the National Museum of Natural History, as well as the National Zoo.Open the full entry’s National Zoo and Conservation Biology Institute and named the institution’s director position the John and Adrienne Mars Director.⁠[4]

In 2025 Mars completed its acquisition of the snack company Kellanova; Forbes records the deal as closing in December 2025 for $35.9 billion including debt.⁠[2][1]

In its March 2026 World’s Billionaires list, Forbes estimated John Mars’s net worth at $49.1 billion; its real-time estimate as of November 4, 2026, was about $50.3 billion. Forbes lists his source of wealth as candy and pet food and his residence as Jackson, Wyoming.⁠[1]

Forbes describes Mars as a $65 billion (sales) business.⁠[1]

Mars credits Forrest E. Mars Jr., John F. Mars and Jacqueline Badger Mars with leading the company’s globalization and with articulating the cultural foundation set by their father as its Five Principles.⁠[2]

The Five Principles—quality, responsibility, mutuality, efficiency and freedom—were the principles by which John Mars and his brother Forrest Jr. ran the company; Forrest Jr. served as co-president of Mars.⁠[3]

Mars has been led by non-family management since 2001 and is headquartered in McLean, Virginia.⁠[2]

John Mars and his wife, Adrienne, are noted supporters of the Smithsonian Institution in Washington, D.C.⁠[1]

Mars: Official website: https://www.mars.com/ (opens in a new window).⁠[2]