Olivier Bouygues

Oliver Bouygues and his billionaire brother, Martin, control over 28% of their eponymous industrial conglomerate Bouygues Group through the holding company SCDM.

The Paris-headquartered giant, which boasts about $70 billion in sales, operates in more than 80 countries in construction, energy, telecoms and media.

Olivier has been on the board of Bouygues since 1984, while his younger brother Martin is chairman of the company.

Their father Frances (d.1993) started the construction firm in 1952. Their mother died in 2017 at age 93.

The brothers own a portfolio of wineries that includes Chateau Montrose, which they purchased in 2006.