who started out as Doriot’ s administrative assistant at ARD, rose to senior vice president and served on the boards of several portfolio companies, becoming one of the leading women in US venture capital.
On the personal side, Doriot was devoted to his wife Edna. He wrote hundreds if not thousands of poems to her, according to former Massachusetts Insurance Commissioner James Stone. He reports that Doriot could not bear to disturb Edna’ s clothes after she died in 1978. They remain in the couple’ s Beacon Hill townhouse, now owned by Stone.
ARD’ s Achievement
From 1946 to 1972, ARD invested in more than 150 companies. Their activities ranged from food processing to electronics, oilfield equipment, water desalination and irradiation.
In its first year, ARD invested approximately $ 200,000 for a stake in High Voltage Engineering( HVEC). The company had its origins in MIT physicist Robert Van de Graaff’ s invention of a high-voltage electrostatic particle accelerator. His colleague John Trump miniaturized the device to administer cancer radiotherapy. Until then, the equipment available for that purpose was unaffordable for most hospitals and it damaged healthy tissues. Trump built several of his compact x-ray generators for local cancer hospitals and obtained further patents for the invention. Following World War II service, Trump teamed with Van de Graaf and British physicist Denis Robinson to start a company to manufacture the new machines. It began production in a Cambridge automobile garage.
During the war, Trump had served alongside ARD co-founder Karl Compton, who introduced him to Doriot. Doriot did not think the cancer treatment machines would be commercially successful, but he was impressed by the HVEC leaders’ technical skills. In addition, Compton made the case that ARD should have a startup with clear human benefits. Doriot accordingly selected HVEC as one of ARD’ s first three investments from more than 400 applications. Both he and Compton joined the new company’ s board.
In 1947, orders began to come in and HVEC’ s business grew as it offered a superior product at a lower price than competitors. By the mid-1950s, however, its
Digital Equipment Corporation( DEC) computer modem, circa mid-1980s.
technology was overtaken in the hospital market by the likes of General Electric. The company therefore focused increasingly on redesigning its generators for applications in research and industry. America’ s response to the Soviet Union’ s 1957 Sputnik launch dramatically increased the commercial demand for nuclear instrumentation. With the Atomic Energy Commission and National Science Foundation bankrolling university and national laboratory purchases of research particle accelerators, HVEC’ s reliable machines became the researchers’ preferred instrument. By 1960, ARD’ s original stake of about $ 200,000 had grown to approximately $ 13.2 million.
That success helped provide capital for further ARD investments. Its biggest winner ever began in the summer of 1957, when two MIT-trained engineers presented a proposal to build a smaller, less expensive computer that could compete with IBM’ s mainframes. Kenneth Olsen and Harlan Anderson were seeking $ 100,000. Only ARD made an offer—$ 70,000 for a 70 % equity stake, with a $ 30,000 loan to follow. Doriot advised Olsen and Anderson to call their company Digital Equipment Corporation( DEC), omitting the word“ computer” from the name on the grounds that it might scare off potential investors in the wake of several computer company failures during the 1950s.
Still avoiding the computer label, DEC launched its PDP( programmed data processor) series in 1960. The company’ s first model was priced at $ 120,000 and represented a major step forward in computing. IBM’ s mainframe required users to submit a punch card to a technician, who delivered the results after a lengthy delay. DEC’ s design enabled users to interact with a computer directly and in real time through a keyboard and monitor.
DEC’ s products were so well received that the company posted a profit in its first year, leading Doriot to lament,“ I’ m sorry to see this— no one has ever succeeded this soon and survived.” As it turned out, he need not have worried. By 1965, DEC had progressed to its PDP-8, the first mass-produced minicomputer, priced at just $ 18,000. DEC ultimately went on to become the largest employer in Massachusetts and the second-biggest US computer manufacturer behind IBM.
In 1966, DEC went public in a stock offering led by Lehman Brothers. ARD’ s stake, 65 % at that point, was worth $ 38.5 million, more than 500 times its original investment. Five years later, the value of ARD’ s holding had soared to $ 355 million.
Retro-Computing Society of Rhode Island
14 FINANCIAL HISTORY | Fall 2026 | www. MoAF. org