Company history

The company has no founder. In October 1939 Tokyo Shibaura Electric — Toshiba — separated its ordnance and machinery operations into a new company, Shibaura Kyomachi Seisakusho, capitalized at ¥5 million; Toshiba took 98% of the shares and Toshiba people held the rest. It borrowed two buildings of the Tsurumi Works in Yokohama along with the machinery inside them, inherited 600 employees from the parent, and in December took over the venerable name of the old Shibaura Seisakusho, the heavy-electrical and ordnance works that had carried it since the Meiji era. There was no president at all at the outset: a serving Toshiba director sat as representative chairman.

Roughly 70% of early output was military. Tsurumi made electromagnetic chucks, motors and aircraft electrical gear; a Kawasaki plant opened in 1940 to build inertia starters and aircraft radio power supplies and was designated a Navy-managed works; the Ofuna plant — today’s Yokohama Works — followed in 1942. In 1943 the company beat Mitsubishi and Matsushita to the Obama plant of Sakai Textile in Fukui by extracting the first permit ever issued by the newly created industrial-facilities authority and producing ¥13.5 million in cash the same day, a piece of improvisation by the accounting chief, Nishino, who later became president.

Defeat took the demand away and left the plant and the payroll. A 1948 fight over redundancies ran from an indefinite strike to a lockout; shareholders’ equity was negative from 1948 through 1950. The company sold the Kawasaki, Omori, Obama and Ofuna plants and their land, at whatever prices a market with few buyers would pay, to fund severance and working capital, and only in 1951 did equity turn positive again.

What rebuilt the company was a household appliance. Toshiba chairman Ishizaka Taizo instructed it to make motors for washing machines and domestic well pumps, and the Obama plant went from two or three thousand units a month around 1952 to 300,000 a month by fiscal 1969 as appliances spread through Japanese homes. Rayon pot motors developed during the war were adopted across the country’s rayon mills and then exported. Through the high-growth decades Shibaura Seisakusho was the group’s machine shop: production equipment for Toshiba’s appliance and component plants, and small motors by the million.

That base was solid enough to float. In October 1969, thirty years after its founding, the company listed on the second section of the Tokyo Stock Exchange, and in February 1972 moved up to the first section — an independent listed company with a captive customer at its back.

The 1980s pushed the motor line upmarket: the RP motor of 1982, thin and long-lived on a proprietary core design, the IC motor of 1983 with its control circuit built in, and stepping motors that found volume in floppy-disk drives and industrial machinery. Vending machines, waterjet cutters and Cartesian robots added revenue. But the more consequential move was quieter: in October 1991 the company merged with Tokuda Seisakusho, a vacuum-equipment specialist, taking its technology in as the vacuum systems division and Sagami plant. That acquisition — not the motors — became the technical foundation of everything that followed. Toshiba still held 61.6% of the stock.

In October 1998 the company merged with Toshiba Mechatronics, a maker of LCD panel production equipment, and changed its name to Shibaura Mechatronics. In the same stroke it separated the motor applications division and part of the Obama plant into Shibaura Densan — 40% Shibaura, 40% Nidec, 20% Toshiba — and transferred to it the appliance and air-conditioner motor business that held some 40% of the domestic market. The motors that had rebuilt the company after the war were, in effect, handed to Nidec; what remained was a three-legged equipment maker in semiconductors, flat panels and electronic components.

The next three years finished the sorting. Vending-machine sales and service moved to a subsidiary by January 2001, manufacturing at Obama to another that October, and the head office consolidated in Yokohama. The rule applied throughout was narrow: keep in the parent only what could be priced through development and assembly, and push the rest across a corporate boundary.

The market did not cooperate. With the dot-com collapse arriving just as the merged functions were being unpicked, net losses ran ¥1.1 billion in the year to March 2002 and ¥1.4 billion the year after. Recovery came fast — ¥5.1 billion of net profit in the year to March 2005 on wafer cleaning and lithography-related demand — but so did the next shock: the Korean subsidiary’s capital was raised to ₩10 billion in 2009 and cut to ₩1.3 billion months later, and the financial crisis drove a net loss of ¥5.5 billion in the year to March 2009. Three legs that all rode the same capital-spending cycle sank together, which is the problem the next decade was spent solving.

Fujita Shigeki took the presidency in June 2013 with a single instruction to himself: stop spreading the risk and concentrate it where the company was actually best. Resources went to semiconductor production equipment — above all single-wafer cleaning tools for the step after chemical-mechanical polishing, a narrow front-end process the company had owned since the Tokuda acquisition. The Fine Mechatronics segment rose from 53% of sales in the year to March 2015 to 59% five years later, and the operating margin climbed from 2.3% to 7.5% over the same span.

In June 2020 Imamura Keigo, who had run the semiconductor equipment division since 2018, succeeded him — an internal promotion that read as a decision to accelerate rather than rebalance. It landed well: sales of ¥44.8 billion and ¥3.0 billion of operating profit in the year to March 2021 became ¥61.0 billion and ¥10.9 billion two years later, with semiconductor equipment operating profit multiplying nearly fivefold. In April 2022 the listing moved to the TSE Prime Market.

Then the shareholder register changed. Toshiba, which had held 36.54% as recently as 2016 and 11.73% after a 2017 restructuring, sold its remaining stake in August 2023 as part of its own reconstruction; by the year to March 2024 it had vanished from the list of principal shareholders, replaced by trust banks and by Shin-Etsu Engineering. Eighty-four years of a single controlling owner ended, and the numbers since have not suffered: ¥67.6 billion of sales and ¥11.7 billion of operating profit in the year to March 2024, ¥80.9 billion and ¥14.1 billion the year after. The company that emerged is an independent world leader in post-polish single-wafer cleaners and in EUV photomask blank cleaning — which leaves it exposed to exactly one question: how well a specialist with no parent absorbs the silicon cycle.