Michael Rubens Bloomberg (born February 14, 1942) is an American businessman and politician. He is the majority owner and co-founder of Bloomberg L.P., and was its CEO from 1981 to 2001, and again from 2014 to 2023. He served as the 109th mayor of New York City from 2002 to 2013. He was a lifelong Democrat until 2001, when he switched to the Republican Party to run for mayor, and later becoming an Independent in 2007. Bloomberg is the most recent mayor of New York City to serve as a Republican or Independent. In 2018, he rejoined the Democratic Party, after which he ran an unsuccessful campaign for the 2020 Democratic nomination for president of the United States. Bloomberg is a centibillionaire, worth $109.4 billion as of March 2026, making him the 18th richest person in the world. Bloomberg grew up in Medford, Massachusetts, and graduated from Johns Hopkins University in Baltimore, Maryland, and Harvard Business School in Boston, Massachusetts. He began his career at the securities brokerage firm Salomon Brothers, before forming his own company in 1981. That company, Bloomberg L.P., is a financial information, software, and media firm that is known for its Bloomberg Terminal. Bloomberg spent the next twenty years as its chairman and CEO. Bloomberg, who has signed the Giving Pledge, has given away $24.5 billion (as of 2025) to philanthropic causes in his lifetime. After a brief stint as a full-time philanthropist, he re-assumed the position of CEO at Bloomberg L.P. by the end of 2014. Bloomberg was elected the 109th mayor of New York City in 2001. He held office for three consecutive terms, winning re-election in 2005 and 2009. Pursuing socially liberal and fiscally moderate policies, Bloomberg developed a technocratic managerial style. As the mayor of New York, Bloomberg established public charter schools, rebuilt urban infrastructure, and supported gun control, public health initiatives, and environmental protections. He also led a re-zoning of large areas of the city, which facilitated widespread new commercial and residential construction after the September 11 attacks. Bloomberg is considered to have had far-reaching influence on the politics, business sector, and culture of New York City during his three terms as mayor. He has also faced significant criticism for the city's stop-and-frisk program, support for which he reversed with an apology before his 2020 presidential run. In November 2019, four months before Super Tuesday, Bloomberg officially launched his campaign for the Democratic nomination for president of the United States in the 2020 election. He ended his campaign in March 2020, after having won only 61 delegates. Bloomberg self-funded $935 million for his candidacy, which set the record for the most expensive presidential primary campaign and highest spending in any political capacity by a single individual in U.S. history. In 2024, Bloomberg received the Presidential Medal of Freedom from President Joe Biden.