Retail is an enormous and profitable industry. Global sales were projected to top $24 trillion in 2015 and are expected to grow another 3.2% this year, making the magnates who run the sector's largest companies even wealthier.
We recently released our list of the 50 richest people on earth based on data from Wealth-X, which conducts research on the super wealthy. Three people in the top 10 are in retail — including the visionaries behind Zara, Amazon, and IKEA — and 12 others cracked the list as well.
To find the wealthiest people in the world, Wealth-X looked at its database of dossiers on more than 110,000 ultra-high net-worth people and used a proprietary valuation model that takes into account each person's assets, then adjusts estimated net worth to account for currency-exchange rates, local taxes, savings rates, investment performance, and other factors. We narrowed that list down to just the billionaires in the retail industry.
Here are the 15 wealthiest people who made their billions in retail:
15. Leonardo Del Vecchio

Net worth:$19.7 billion
Age: 80
Country: Italy
Source of wealth: Self-made, Luxottica Group
Even at 80, Leonardo Del Vecchio still chairs Luxottica, the nearly $30 billion company he founded in 1961. The largest eyewear company on the planet, Luxottica not only owns Sunglass Hut, Ray-Ban, and Oakley, but also manufacturers glasses for nearly every luxury brand out there, including Burberry, Chanel, Prada, and Versace.
Though Del Vecchio started Luxottica as a tiny one-room enterprise in Milan, it now operates 10 factories worldwide, employs 35,000 people, and produces more than 65,000 pairs of glasses per day, holding a veritable monopoly on the eyewear industry.
Del Vecchio isn't all business, though. Last March, he showed his generous side by giving his Italian employees $10 million worth of shares in the company to celebrate his 80th birthday.
14. Dieter Schwarz

Net worth:$20.9 billion
Age: 76
Country: Germany
Source of wealth: Inheritance/self-made, Schwarz Gruppe
Dieter Schwarz joined his father's food-wholesaling business in 1973 and opened the company's first discount supermarket shortly thereafter. He took over as CEO when his father died in 1977 and rapidly expanded the business outside Germany, rebranding the company as Schwarz Gruppe.
The parent company umbrellas Lidl, a successful grocery-store chain and the second largest in Germany behind Aldi, and Kaufland, a chain of "hypermarket" stores similar to Walmart. Lidl has nearly 10,000 stores across 26 European countries and is set to break ground on US soil in 2018. Schwarz Gruppe now pulls in $85 billion in annual sales.
The German billionaire lives a quiet life out of the spotlight with his wife and two kids in their hometown of Heilbronn. He's reportedly a generous donor to educational causes.
13. Phil Knight

Net worth:$25.7 billion
Age: 77
Country: US
Source of wealth: Self-made, Nike
After a stint in the US Army, and with a Stanford MBA under his belt, Phil Knight convinced Tiger-brand shoemaker Onitsuka in the early 1960s to allow him to distribute Tiger shoes under the name Blue Ribbon Sports — the name Knight picked that predated his swoosh-logo-clad company Nike. Knight worked full-time as an accountant as he launched his new brand, and by 1968 he had built up enough of a rapport with customers that he was able to leave the CPA life behind.
Nike has built its success on celebrity and athlete-endorsement deals, starting with running prodigy Steve Prefontaine in 1973 and continuing with one of the most successful shoe marketers of all time in Michael Jordan. Nike signed him to a five-year endorsement deal in 1984 worth roughly $500,000 per year. The biggest NBA star today is still under the Nike roof, with LeBron James signing a lifetime contract with the brand in December for an undisclosed sum.
Though Knight announced plans in June to step down as Nike chairman, he's leaving the $30.6 billion — in sales — company in better shape than ever, with the stock and revenues at all-time highs.
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