X avier Niel is a self-made French billionaire who is a revolutionary and iconoclastic figure in the country's telecommunications and technology industries. He started his first business as a teenager and made his first fortune by founding Worldnet, France's first internet service provider, which he later sold. His career-defining move came in 2012 with the launch of Free Mobile. He radically disrupted the cozy French mobile market, which was dominated by three established players, by offering a simple, low-cost mobile plan that was a fraction of the price of his competitors. This move upended the industry and won him millions of subscribers.

His telecom and internet businesses are held under his publicly traded company, Iliad. Beyond telecom, Niel is a prolific and influential technology investor through his private investment firm, Kima Ventures, which is one of the most active angel investors in the world. He is also a major figure in education, having founded the innovative, tuition-free coding school, Station F, which is the world's largest startup campus, located in Paris. He also has significant holdings in the media, including co-ownership of the newspaper Le Monde.