The Koch brothers are two of the richest men in the world. Charles and David Koch each have a net worth of $53.7 billion, according to Forbes. Their fortunes come from their 42% stakes in the Koch family business: Koch Industries. Charles is currently the company's president and CEO, while David just announced that he was retiring from the firm. The Koch brothers are two of the richest people on planet earth. Charles and David Koch tied for eighth on Forbes' 2018 list of the wealthiest billionaires in the world.