The 16 richest Americans in the Bloomberg Billionaires Index and Forbes Billionaires List are collectively worth more than US$1 trillion. While tech moguls continue to dominate the top ranks, inherited wealth, like in the Walton family, also makes a strong appearance in the list. The four richest people in America are also the richest people in the world, with Jeff Bezos continuing to rank first – after his personal wealth increased dramatically since the coronavirus pandemic . 16. Michael Bloomberg Net worth: US$54.9 billion (per Forbes estimates) Age: 78 Industry: finance, technology Source of wealth: self-made; Bloomberg LP Net worth year-over-year change: not readily available Michael Bloomberg, former Democratic presidential candidate and long-time New York City mayor, derives a majority of his wealth from his financial services company, Bloomberg LP. In the 1990s, he expanded the company to form Bloomberg News and TV. His eponymous company currently makes about US$10 billion in annual revenue and Bloomberg maintains control over 88 per cent of the company. Bloomberg is fairly generous with his wealth and is known to donate to social issues like gun control and climate change. He donated more than US$3 billion of his fortune in 2019 alone. Why are all these billionaires wearing watches that even you can afford? 15. Charles Koch Net worth: US$56.6 billion Age: 84 Industry: diversified investments Source of wealth: self-made; Koch Industries Net worth year-over-year change: down US$5.40 billion in the past year Charles Koch is chairman and CEO of multifaceted conglomerate Koch Industries, the second-largest private company in America. The company employs 130,000 people and generates an estimated US$110 billion in annual revenue from its diverse holdings, which make everything from petrochemicals and Dixie Cups to raw clothing materials. Koch is outspoken in the world of conservative politics and public policy. Koch and late younger brother, David, have long been known as advocates for smaller government and routinely fund political campaigns, although they took a step back during the 2016 election cycle. The book Dark Money: The Hidden History of the Billionaires Behind the Rise of the Radical Right revealed that Charles Koch’s plans to reshape American politics date back 40 years, when he began strategising and developing a libertarian movement. 15. Julia Flesher Koch Net worth: US$56.6 billion Age: 57 Industry: industrial Source of wealth: inheritance; Koch Industries Net worth year-over-year change: down US$5.40 billion in the last year Flesher Koch was married to David Koch, one of the richest men in America, for 23 years until his death in 2019. They met after being set up on a blind date by a mutual friend. According to Forbes estimates, her net worth is closer to US$45 billion. Business Insider previously reported that this discrepancy might be due to the difference in estimates of how much Koch left to his children as well as differences in the net worth of Koch Industries. 13. Alice Walton Net worth: US$60.4 billion Age: 70 Industry: retail Source of wealth: inheritance; Walmart Net worth year-over-year change: up by US$7.39 billion over the last year The daughter of late Walmart founder Sam Walton, Alice Walton holds a major piece of the company fortune, making her one of the richest women on earth. Though she never took an active role in running the superstore like her brothers, she’s become the target of resistance from minimum-wage Walmart employees who view her lifestyle as insensitive to the plights of workers. Walton has become a patron of the arts. Her immense personal collection includes pieces from Andy Warhol, Norman Rockwell and Georgia O’Keefe. In 2011, she opened the US$50 million Crystal Bridges Museum in Arkansas, where a number of her famous paintings are on display. In 2015, Walton donated 3.7 million of her Walmart shares to the family’s non-profit and put her Texas ranches – one a working horse ranch, the other a luxurious holiday spot – on the market for a combined US$48 million. The world’s 25 wealthiest family business empires ranked 12. Jim Walton Net worth: US$61 billion Age: 72 Industry: retail Source of wealth: inheritance; Walmart Net worth year-over-year change: up by US$6.95 billion over the last year James “Jim” Walton’s parents, Helen and Sam Walton, bought a controlling stake in Arkansas’ Bank of Bentonville the year before opening the first Walmart store in Rogers, Arkansas, in 1962. Within five years, the family owned 24 of the retail stores and in 1972 listed Walmart on the New York Stock Exchange. In 1975, after working in Walmart’s real-estate department for a few years, Jim joined his parents’ bank, later renamed Arvest Bank Group. He’s now chairman and CEO of the regional community bank, which has US$15 billion in assets. Over the last year, Walton’s has increased by US$2.7 billion. The businessman is also director of Walton Enterprises, the holding company for the Walton family assets, and chairman of Community Publishers, an Arkansas-based newspaper firm. After the death of his brother John in 2005, Jim joined the board of Walmart, where he serves as a director today. While America’s richest family remains private, the Walton Family Foundation, of which Jim is secretary and treasurer, has donated millions to charitable causes. In December 2015, Jim and his siblings donated US$407 million worth of Walmart shares to a newly formed trust that funds the Waltons’ philanthropy, which focuses on educational, cultural, community development, and social causes. In July 2019, Walton donated US$1.2 billion in stocks. 11. Rob Walton Net worth: US$61.2 billion Age: 75 Industry: retail Source of wealth: inheritance; Walmart Net worth year-over-year change: up by US$7 billion over the last year Samuel Robson “Rob” Walton is the oldest son of Walmart founder Sam Walton. He started working at the retail behemoth in 1969, holding positions from senior vice-president to general counsel to chairman, a role he stepped down from in June 2015 after 23 years on the job. His son-in-law was named as his successor. In July 2019, Walton donated 135,000 shares worth US$15 million to an anonymous recipient. Regulatory filings on New Year‘s Eve 2016 revealed that Walton and his brother each gave away 1.5 million Walmart shares to the family charity, Walton Family Holdings Trust, while sister Alice gave away 3.7 million shares, for a total family donation of US$407 million. It’s an incredible amount, but it’s also ultimately a drop in the bucket for the Waltons. 10. MacKenzie Scott Net worth: US$66.4 billion Age: 50 Industry: technology Source of wealth: self-made; Amazon Net worth year-over-year change: up by US$29.3 billion over the last year MacKenzie Scott, a Princeton graduate and former assistant to famed American essayist Toni Morrison, owns a four per cent stake in e-commerce giant Amazon. Scott was married to Jeff Bezos for more than 25 years before divorcing in 2019. She gained her stake in Amazon as part of the divorce settlement. The New York Times wrote that Scott “was Amazon’s first accountant and was involved in its transformation from a small online bookseller to the e-commerce behemoth it is today.” On July 28, Scott donated US$1.7 billion to more than a hundred different organisations working towards a number of different social issues. She made all of the money back within days. Mark Zuckerberg: how the world’s third-richest man spends his billions 9. Larry Ellison Net worth: US$69.5 billion Age: 75 Industry: technology Source of wealth: self-made; Oracle Net worth year-over-year change: up by US$10.8 billion over the last year In 1977, Larry Ellison teamed up with two colleagues from an electronics company to start their own programming firm, which landed a contract not long after to build a relational database-management system for the CIA under the project code Oracle. The project grew into what is known today as Oracle Corp., currently valued at US$170.31 billion. In 2010, Ellison reduced his annual salary from US$1 million to US$1, but he still takes in more than $60 million in total compensation thanks to generous stock awards. Ellison stepped down as CEO in 2014 after 38 years on the job and took on the role of chief technology officer. The tech tycoon is also a generous philanthropist through partnerships with wildlife conservation groups and the Lawrence Ellison Foundation, which supports organisations that research ageing and global infectious diseases. He‘s also a member of Bill Gates’ and Warren Buffett’s Giving Pledge, committing to give away at least half of his fortune. 8. Sergey Brin Net worth: US$74.9 billion Age: 46 Industry: technology Source of wealth: self-made; Google Net worth year-over-year change: up by US$12.2 billion over the last year Along with co-founder Larry Page, Sergey Brin helped facilitate Google‘s massive restructuring, which the company announced in 2015. The move put Google under the auspices of holding company Alphabet, run by Brin as president and Page as CEO. Google’s other ventures, such as Nest and Google X, are separate companies also under the Alphabet umbrella. The restructuring allowed Brin to focus on exploring inventive new “moon shot” projects and ideas. With top talent and an abundance of resources at its disposal, Alphabet has already made automated homes and self-driving cars a reality. Brin, who emigrated from Moscow to the US as a child, connected with Page in 1995 at Stanford, where they were each pursuing a PhD. Three years later they founded Google, now one of the most powerful companies on the planet. 7. Larry Page Net worth: US$77.3 billion Age: 47 Industry: technology Source of wealth: self-made; Google Net worth year-over-year change: up by US$12.7 billion over the last year As a Stanford PhD student in 1998, Larry Page teamed up with classmate Sergey Brin to create BackRub, an early search engine. The project eventually morphed into Google. In January 2020, Alphabet, Google’s parent company, was valued at US$1 trillion, the third tech company to gain that status after Apple and Amazon. Page oversaw major changes to Google’s business structure in 2015, starting with the creation of Alphabet, the holding company that manages Google and all of its related ventures, including Nest, Calico and Google X. Previously the chief executive of Google, Page moved up to helm Alphabet, which has its hands in everything from home automation to self-driving cars to prolonging human life. Page doesn’t make a lot of splashy purchases, but the alternative-energy advocate does own an eco-friendly mansion in Palo Alto that uses geothermal energy and rainwater capture. He’s also an avid kiteboarder. Why hasn’t Jeff Bezos donated as much to charity as other billionaires? 6. Steve Ballmer Net worth: US$80.8 billion Age: 64 Industry: technology Source of wealth: self-made; Microsoft Net worth year-over-year change: up by US$22.7 billion over the last year Steve Ballmer dropped out of business school at Stanford in 1980 to join Harvard friend Bill Gates at Microsoft as the company’s first business manager, earning a US$50,000 salary and a stake in the company. During his tenure, Ballmer held positions as vice-president of marketing, vice-president of systems software, and executive vice-president of sales and support, and was often referred to as “the numbers guy”. He became CEO of the company in 2000 after Gates stepped down, and he remained in charge of the software giant until Satya Nadella replaced him in 2014. While running Microsoft, the company‘s revenue grew by 294 per cent and profits by 181 per cent – although its market share was surpassed by Google and Apple during the same period. Still, the early stake Ballmer acquired in the company made him immensely wealthy. After stepping down as CEO, Ballmer fulfilled his dream of owning an NBA franchise, paying US$2 billion in a deal to buy the Los Angeles Clippers. Ballmer runs The Ballmer Group with his wife, Connie. The group works to help economically-disadvantaged people and families in the US. 5. Warren Buffett Net worth: US$82.5 billion Age: 89 Industry: diversified investments Source of wealth: self-made; Berkshire Hathaway Net worth year-over-year change: down by US$6.73 billion over the last year Berkshire Hathaway CEO Warren Buffett started his prodigious investing career at a young age. As a child he delivered newspapers on his bike, and by 11 the Nebraska native had bought his first shares in the stock market – Cities Service Preferred at US$38 apiece – and sold them for a US$5 profit. He was rejected from Harvard Business School, so Buffett went to Columbia Business School instead and learned under iconic value investor Benjamin Graham, who would become a mentor to the budding financier. Buffett worked as a securities analyst in the early 1950s before starting his own investment firm. He bought textile company Berkshire Hathaway in 1969, transforming it into a holding company that would house the many lucrative investments that helped build his massive fortune and earn the nickname “The Oracle of Omaha”. The array of portfolio companies and investments that made him rich may appear random – he’s bet on companies including Coca-Cola, American Express, Geico, Fruit of the Loom, Dairy Queen and General Motors – but they’re all cash-generating machines that offer long-term value. A frugal man with a fondness for junk food, perhaps the most impressive part of Buffett’s US$60 billion fortune is that it doesn’t include the US$37 billion he’s already given away. He’s good friends with Microsoft co-founder Bill Gates, with whom he collaborated to create the Giving Pledge, a promise for billionaires to give away at least half of their wealth to charity. 4. Mark Zuckerberg Net worth: US$111 billion Age: 36 Industry: technology Source of wealth: self-made; Facebook Net worth year-over-year change: up by US$32.4 billion over the last year In 2004, Mark Zuckerberg, then a 19-year-old sophomore at Harvard, launched TheFacebook.com, a rudimentary version of the now-ubiquitous social network known as Facebook. Zuckerberg dropped out of college to work full-time as Facebook’s CEO, and the site exploded in popularity. At 36, Zuckerberg is one of the youngest of the 50 richest people in the world. In December 2015, Zuckerberg and his wife Priscilla Chan pledged to give away 99 per cent of their wealth in their lifetimes through an organisation called the Chan Zuckerberg Initiative, though some critics noted the organisation wasn’t a non-profit charity itself and found the announcement misleading. The couple also donated US$25 million in the fight against Ebola in 2015 and they gave US$100 million worth of Facebook shares toward improving a New Jersey public-school system. How do tech billionaires splash out on their superyachts? 3. Elon Musk Net worth: US$115 billion Age: 49 Industry: technology Source of wealth: self-made; Tesla Net worth year-over-year change: up by US$87.8 billion over the last year Before gaining fame as the flashy CEO of Tesla, Musk dabbled in a number of business ventures, from designing games to running nightclubs out of a frat house. Musk has a degree in physics and economics from the University of Pennsylvania and attended Stanford University for a PhD before ultimately dropping out. Musk is best known for being in leadership roles at electric vehicle company Tesla and aerospace company SpaceX, valued at US$277 billion and US$36 billion respectively. In August 2020, SpaceX conducted a successful test flight for a prototype rocket for its Mars mission. “Mars is looking real,” Musk tweeted soon after. Musk is a part of The Giving Pledge, a non-profit consisting of some of the world‘s wealthiest individuals who’ve committed significant portions of their wealth to charity. He also runs the Musk Foundation, through which he’s donated to artificial intelligence research, advocacy groups, schools his children attend and art projects at Burning Man festival. Who is Jennifer Gates, daughter of Melinda and Bill Gates? 2. Bill Gates Net worth: US$125 billion Age: 64 Industry: technology Source of wealth: self-made; Microsoft Net worth year-over-year change: up by US$11.7 billion over the last year At just 20, Bill Gates co-founded Microsoft with his childhood friend Paul Allen. Months before his 31st birthday, the company went public, making Gates a billionaire. He served as CEO of the software titan until 2000 and was its chairman and largest shareholder until 2014. Though he still sits on the company’s board, Gates is no longer actively involved in Microsoft. Gates is not only one of the richest people in the world, but he’s also one of the most generous. Since 1999, Gates and his wife have helmed the Bill & Melinda Gates Foundation, one of the most powerful charities in the world. The foundation – which controls an endowment of more than US$46 billion – aims to lift millions of people out of poverty, with a heavy focus on eliminating HIV, malaria and other infectious diseases. The Gates Foundation recently teamed up with India-based biomedical company Serum Institute to produce low-price coronavirus vaccines. Earlier in the spring, the foundation, along with Mastercard and Wellcome, committed US$125 million to fight the epidemic. Gates is also co-founder of the Giving Pledge, which he launched in 2010 with friend and fellow billionaire Warren Buffett as a promise to donate 50 per cent or more of their fortunes. The Giving Pledge now counts Mark Zuckerberg and Elon Musk among its 204 members. The 8 biggest tech rivalries to shake up Silicon Valley 1. Jeff Bezos Net worth: US$202 billion Age: 56 Industry: technology Source of wealth: self-made; Amazon Net worth year-over-year change: up by US$87.6 billion over the last year Jeff Bezos earned his massive fortune by introducing e-commerce to the world. After spending time in finance on Wall Street, Bezos founded Amazon in the garage of his Seattle home in 1994 and operated it exclusively as an online book retailer. The company went public three years later and has since grown to include everything from furniture to food to Amazon’s own consumer electronics products. Bezos also has interests outside Amazon, including investments in his privately owned space company Blue Origin, which successfully launched its first spacecraft in 2015, and The Washington Post , the newspaper he bought in 2013. Want more stories like this? Sign up here . Follow STYLE on Facebook , Instagram , YouTube and Twitter . This article originally appeared on Business Insider