- Source of Wealth: Business – IMC International Metalworking Companies B.V., otherwise known as IMC Group (one of the world’s largest (by sales) manufacturers of carbide industrial-cutting tools)
- Age: 93
- Birth Place: Kippenheim, Germany
- Marital Status: Married
- Full Name: Stef Wertheimer
- Nationality: Israeli
- Date of Birth: July 16, 1926
- Ethnicity: German
- Occupation: Businessman (Honorary chairman of IMC International Metalworking Companies B.V., otherwise known as IMC Group)
- Education: Tel-Nordau School
- Children: 4
Stef Wertheimer rose to fame in 2006 when his business became the first international target of Berkshire Hathaway Inc., where Warren Buffet sits as the Chairman, President, CEO, and co-founder. Stef Wertheimer has an estimated net worth of $5.7 billion.
Stef Wertheimer started working in a metal tool cutting factory in Israel which has now evolved into one of the world’s largest manufacturers and producers of carbide-industrial cutting tools. Today, the company operates in over 50 countries worldwide and employs more than 6,000 people. Wertheimer is also the founder of Blades Technology Ltd. which specializes in manufacturing vanes and blades for industrial gas turbines and jet engines.
In 2006, Berkshire Hathaway Inc. bought 80% stake of ISCAR Metalworking Company for $5 billion. Today, the Wertheimer family runs the $1 billion worth Blades Technology Ltd. which was not included in the purchase deal between Wertheimer and Berkshire Hathaway Inc.