The Wertheimer Family: Iscar, Berkshire, and the $6 Billion Sale of the Israeli Industrial Century

The Wertheimer family built and sold Iscar — the metal-cutting-tools business founded by Stef Wertheimer (1926–2025) in a shack in Nahariya in 1952 — to Berkshire Hathaway in two stages between 2006 and 2013 for a total of approximately $6.05 billion. The first transaction, in May 2006, sold 80 percent for $4 billion, valuing the parent IMC group at $5 billion — Berkshire's first major overseas acquisition. The second, in April 2013, completed the deal at $2.05 billion for the remaining 20 percent, giving Berkshire 100 percent ownership. Iscar is the most-valuable Israeli family business ever sold. Iscar remains headquartered at Migdal Tefen in the Western Galilee, alongside the industrial-park complex Stef Wertheimer built as the physical infrastructure of his Zionist industrial thesis.

Stef Wertheimer, 1926–2025

Stef Wertheimer was born in Germany in 1926 and immigrated to Mandatory Palestine in 1937. He served in the Palmach during the pre-state period. In 1952, at age 26, he founded Iscar in an old shack in the coastal city of Nahariya together with his wife Miriam. The founding product line was metal-cutting inserts and precision tooling for machined manufacturing.

He died in 2025. At death, Forbes estimated his net worth at approximately $7.6 billion, making him consistently one of the wealthiest Israelis on the Forbes list.

The Tefen Industrial Park and the Wertheimer Industrial-Zionism Thesis

Stef Wertheimer's political and industrial vision — that Israel's peripheral development depended on export-oriented industrial parks that combined manufacturing with education, community, and culture — is embodied in the Tefen Industrial Park he built in the Western Galilee in 1985. Iscar's operations relocated from Nahariya to Migdal Tefen in 1982, becoming the anchor tenant of what would become a broader industrial-community complex.

Tefen looks less like a factory zone than a college campus: trim lawns, garden sculptures, a museum of modern art, a collection of vintage cars, a shared dining hall, a tennis court, and an alternative school educating more than 500 students of various ages in industry and creativity. The residential community Kfar Vradim, which Wertheimer established in 1981 — the same year he ended a four-year stint in the Knesset (1977–1981) — sits five minutes from the park and became the entrepreneur-magnet housing that pulled talent to Tefen.

Wertheimer founded seven industrial parks on the same principles — exports, education, coexistence, community, and culture: Tefen, Tel Hai, Dalton, Lavon, and Nazareth in the Galilee; Omer in the Negev; and Gebze in Kocaeli, Turkey. The family has spent more than $100 million to build Arab-Jewish integrated industrial workspaces around Israel — the practical civic corollary of the "coexistence" pillar. Wertheimer received the Oslo Business for Peace Award in 2010.

Eitan Wertheimer and the Berkshire Deal

Stef's son Eitan Wertheimer took over day-to-day operations of Iscar in 2004 and became the family principal in the negotiation with Warren Buffett. The story Eitan has recounted: he decided he wanted to sell, and there was only one buyer he wanted — Buffett.

The transaction was announced on May 5, 2006. Berkshire Hathaway agreed to acquire 80 percent of the Iscar Metalworking Companies (IMC) — the parent holding company incorporated in the Netherlands (IMC International Metalworking Companies B.V.) that owned Iscar, TaeguTec (Korea), Ingersoll, and other subsidiaries — in a transaction that valued IMC at $5 billion. The 80 percent purchase price was $4 billion. The Wertheimer family retained the remaining 20 percent. The deal closed on July 5, 2006. The Wertheimers reportedly paid approximately $1 billion in Israeli taxes on the transaction.

The 2006 transaction was Berkshire Hathaway's first major overseas acquisition. Buffett publicly praised IMC's management and business model as "simple and profitable" with significant growth prospects, and Iscar retained its Tefen headquarters and its existing worldwide management team including chairman Eitan Wertheimer and president and CEO Jacob Harpaz.

Seven years later, on April 29, 2013, Berkshire acquired the remaining 20 percent of IMC from the Wertheimer family for $2.05 billion, taking IMC to 100 percent Berkshire ownership. Eitan Wertheimer stated the growth of the business since 2006 had validated Buffett's original commitment; the Wertheimer family's decision to exit the residual position placed IMC as a permanent Berkshire holding.

Blades Technology and the 2014 Pratt & Whitney Deal

Alongside Iscar, Stef Wertheimer founded Blades Technology, a manufacturer of jet-engine blades and components. In 2014, he sold his 51 percent stake to Pratt & Whitney, the U.S. jet-engine maker, for an undisclosed amount. The Blades transaction extended the family's exit from precision-industrial manufacturing beyond Iscar into aviation propulsion.

Iscar Today Under Berkshire

ISCAR Ltd. remains headquartered at Migdal Tefen and is the leading brand within IMC — a network of more than 150 subsidiaries in over 60 countries. The current Iscar CEO is Ilan Geri. IMC Group Chairman is Jacob Harpaz. Product coverage spans turning, milling, holemaking, threading, parting and grooving — deployed by manufacturers in aerospace, automotive, energy, medical, and general engineering. IMC is one of Berkshire Hathaway's largest non-insurance businesses.

Why the Wertheimer Family Matters to Israeli Business History

Iscar is the largest and most-valuable Israeli family business ever sold — $6.05 billion in total consideration to Berkshire Hathaway between 2006 and 2013, at a time when nine-figure Israeli exits were the ceiling. The transaction validated Israeli industrial manufacturing at a moment when Israeli venture-capital narratives were consolidating around software and cyber. Stef Wertheimer's parallel thesis — that periphery development requires export-oriented industrial parks with cultural and educational anchors — remains the operating model at Tefen and the six other parks the family built.

The Wertheimer family sits alongside the Ofer, Tshuva, Federmann, and Arison families as one of the small number of Israeli multi-generational fortunes at multi-billion-dollar scale. Unlike most of that peer group, the Wertheimers built through operating industrial manufacturing rather than shipping, real estate, hotels, or financial services.

For adjacent Israeli founder profiles and kibbutz-industrial exits, see Tnuva and Naot / Neot Mordechai. On the Israeli capital-markets founders operating through the same period, see Zvi Stepak and Joseph Hackmey.

Frequently Asked Questions

Who is the Wertheimer family?
An Israeli industrial family, founders of Iscar Ltd. (metal-cutting tools) in 1952 in Nahariya. Patriarch Stef Wertheimer (1926–2025), his wife Miriam, and their son Eitan built Iscar into the largest metal-cutting-tools franchise in Israel and one of the largest in the world.

How much did Berkshire pay for Iscar?
Approximately $6.05 billion in total across two transactions. In May 2006, Berkshire paid $4 billion for 80 percent of IMC at a $5 billion enterprise valuation. In April 2013, Berkshire paid $2.05 billion for the remaining 20 percent, making Iscar 100 percent Berkshire-owned. It was Berkshire Hathaway's first major overseas acquisition.

Where is Iscar headquartered?
Migdal Tefen in Israel's Western Galilee — the industrial-park complex Stef Wertheimer built in 1985 as the anchor of his industrial-Zionist thesis. Iscar relocated to Tefen from Nahariya in 1982.

What are the Wertheimer industrial parks?
Seven parks on the principles of exports, education, coexistence, community, and culture: Tefen, Tel Hai, Dalton, Lavon, and Nazareth in the Galilee; Omer in the Negev; and Gebze in Kocaeli, Turkey. The family has spent more than $100 million on Arab-Jewish integrated industrial workspaces.

Who runs Iscar today?
CEO Ilan Geri. IMC Group Chairman Jacob Harpaz. Iscar is part of IMC, a network of more than 150 subsidiaries in over 60 countries, wholly owned by Berkshire Hathaway.