As outlined by Statista:
Successful business enterprises are they key to the wealth of the world’s richest families. According to a ranking by Bloomberg, three American families top the ranking of the world’s wealthiest. The top 2 – The Waltons and the Mars family – deal in consumer goods, while the Kochs in rank 3 are more of an industrialist clan. The Walton family’s assets come to $238 billion, while the Mars family made a fortune of $142 billion from their empire of brands such as Milky Way, Snickers, M&M’s, Twix and Wrigley chewing gum.