Isabel Boehringer

Isabel Boehringer derives her fortune from Boehringer Ingelheim, the world's largest private pharmaceutical company.

Founded by Albert Boehringer in 1885, the company made ingredients for pharmacies, textile merchants and the food industry and grew to a workforce of 1,500 by the time of his death.

Today some of the company's most well-known drugs treat COPD, anti-coagulation and type 2 diabetes.

Boehringer Ingelheim now employs 53,000 people and has a presence in 130 markets.

Isabel and 14 members of the family -- all in the third, fourth or fifth generation -- own equal parts of the company.