Francoise Bettencourt Meyers became the first woman to amass a $100 billion fortune, marking another milestone for the heiress and for France's expanding fashion and cosmetics industries.
Her wealth jumped to $100.1 billion on Thursday, according to the Bloomberg Billionaires Index.
The milestone came as shares of L'Oréal SA, the beauty products empire founded by her grandfather, rose to a record high, with the stock set for its best year since 1998.
She's the 12th-richest person in the world, just behind Mexico's Carlos Slim.
Despite the gain, Bettencourt Meyers' fortune is still significantly less than that of French compatriot Bernard Arnault, founder of luxury goods purveyor LVMH Moet Hennessy Louis Vuitton SE, who is second in the global ranking with $179 billion.
France's growing domination of luxury retail has spawned several other ultra-rich families, including the clan behind Hermes International SCA, who have amassed Europe's largest family fortune, and the Wertheimer brothers who own Chanel.
The reclusive Bettencourt Meyers, 70, is vice-chair of the board of L'Oréal, a globe-spanning €241 billion ($268 billion) company in which she and her family are the single biggest shareholders with a stake of nearly 35%.
Her sons, Jean-Victor Meyers and Nicolas Meyers, are also directors.
Run by executives from outside the family for decades, the firm was founded in 1909 by Bettencourt Meyers' chemist grandfather, Eugene Schueller, to produce and sell a hair dye he had developed.
Bettencourt Meyers keeps her life private, shunning the glitzy social life sought by many the world's wealthy. She has written two books — a five-volume study of the Bible and a genealogy of the Greek gods — and is known for playing piano for hours every day.