The business story
Born in Kippenheim, Germany, in 1926; his family fled Nazi Germany for Mandatory Palestine in 1937. Largely self-taught, with no university degree; an RAF technical contractor in WWII and a Palmach member. Founded ISCAR in 1952 as a backyard metal shop in Nahariya and built it into the IMC Group, a multinational maker of carbide cutting tools. Built the Tefen Industrial Park (1982). Berkshire Hathaway bought 80% of IMC in 2006 (~$4B) and the rest in 2013 (~$2.05B). A Knesset member 1977–1981. Died 26 March 2025, aged 98.
Wertheimer's approach was a builder's theory applied consistently: make real things, create skilled jobs, and the wider benefits will follow.
Early life and background
Stef Wertheimer was born on 16 July 1926 in Kippenheim, a small town in Baden, Germany, into a Jewish family. In 1937, as Nazi persecution intensified, the family left for Mandatory Palestine. He was around eleven, and the move almost certainly saved their lives.
He never earned a university degree. His education was practical and mostly self-directed: he learned how machines worked by building and repairing them. During the Second World War he worked as a technical contractor for Britain's Royal Air Force, and he served in the Palmach, the elite strike force of the pre-state Jewish underground. Both experiences grounded him in precision mechanics and in the stakes of the national project around him.
Building ISCAR
In 1952, when Israel was four years old and short of nearly everything, Wertheimer set up a metalworking shop behind his home in Nahariya, a northern coastal town near the Lebanese border. He called it ISCAR. At first it was just him, making carbide cutting tools: the inserts and tooling machine shops use to cut, mill and shape metal.
It is an unglamorous product sold to demanding industrial buyers, with no brand halo or network effects to lean on. A tool either holds its tolerance and outlasts the alternatives or it loses the order. Competing from Nahariya meant beating established manufacturers in Europe, the United States and Japan on engineering and quality, and over decades ISCAR did. It became known for new insert designs, geometries and coatings, and grew into the Iscar Metalworking Companies, later the IMC Group.
In 1968 he founded ISCAR Blades, later Blades Technology, which makes jet-engine components, some of the most exacting precision work in manufacturing.
Outside confirmation came in 2006, when Berkshire Hathaway bought 80 percent of IMC for about $4 billion. It was Warren Buffett's first acquisition of a company based outside the US. In 2013 Berkshire bought the remaining stake for roughly $2.05 billion, a deal that valued the business above $10 billion. Wertheimer's net worth was estimated at around $7.6 billion.
