The son of a Bulgarian immigrant who became an electrical engineer, Atanasoff held positions as a teaching professor, a governmental wartime research director, and a corporate research executive before being recognized in the 1970s and 1980s for digital electronic computer research he conducted at Iowa State College in the late 1930s and early 1940s.
Atanasoff was raised by his parents in Brewster, Florida. At the age of nine he learned to use a slide rule, followed shortly by the study of logarithms, and subsequently completed high school at Mulberry High School in two years. In 1925, Atanasoff received his bachelor of science degree in electrical engineering from the University of Florida, graduating with straight A's.
He continued his education at Iowa State College and in 1926 earned a master's degree in mathematics. He completed his formal education in 1930 by earning a Ph.D. in theoretical physics from the University of Wisconsin-Madison with his thesis, The Dielectric Constant of Helium. Upon completion of his doctorate, Atanasoff accepted an assistant professorship at Iowa State College in mathematics and physics.
Partly due to the drudgery of using the mechanical Monroe calculator, which was the best tool available to him while he was writing his doctoral thesis, Atanasoff began to search for faster methods of computation. At Iowa State, Atanasoff researched the use of slaved Monroe calculators and IBM tabulators for scientific problems. In 1936 he invented an analog calculator for analyzing surface geometry. The fine mechanical tolerance required for good accuracy pushed him to consider digital solutions.
According to Atanasoff, several operative principles of the Atanasoff–Berry Computer (ABC) were conceived by the professor in a flash of insight during the winter of 1937–1938 after a drive to Rock Island, Illinois. With a grant of $650 received in September 1939 and the assistance of his graduate student Clifford Berry, the ABC was prototyped by November of that year.
The key ideas employed in the ABC included binary math and Boolean logic to solve up to 29 simultaneous linear equations. The ABC had no central processing unit (CPU), but was designed as an electronic device using vacuum tubes for digital computation. It also used separate regenerative capacitor memory, a process still used today in DRAM memory.
In June 1941 Mauchly visited Atanasoff in Ames, Iowa to see the ABC. During his four day visit as Atanasoff's houseguest, Mauchly thoroughly discussed the prototype ABC, examined it, and reviewed Atanasoff's design manuscript in detail. Up to this time Mauchly had not proposed a digital computer. In September 1942 Atanasoff left Iowa State for a wartime assignment as Chief of the Acoustic Division with the Naval Ordnance Laboratory (NOL) in Washington D.C. He entrusted his patent application for the ABC to Iowa State College administrators. It was never filed.
Mauchly visited Atanasoff multiple times in Washington during 1943 and discussed Atanasoff's computing theories, but did not mention that he was working on a computer project himself until early 1944. John Mauchly and J. Presper Eckert's construction of ENIAC, the first general purpose electronic computer, during 1943–1946 was to lead to a legal dispute two decades later over who was the actual inventor of the computer.
By 1945 the U.S. Navy, too, had decided to build a large scale computer, on the advice of John von Neumann. Atanasoff was put in charge of the project, and he asked Mauchly to help with job descriptions for the necessary staff. However, Atanasoff was also given the responsibility for designing acoustic systems for monitoring atomic bomb tests. That job was made the priority, and by the time he returned from the testing at Bikini Atoll in July 1946, the NOL computer project was shut down due to lack of progress, again on the advice of von Neumann.
Mauchly and Eckert applied for a patent on a "General-Purpose Electronic Computer" in 1947, which was finally granted in 1964. The rights to the patent had been sold in 1951 to Remington Rand (to become Sperry Rand); that company created a subsidiary (Illinois Scientific Developments) to start demanding royalty payments from other equipment manufacturers in the electronic data processing industry in the 1960s.
In June 1954 IBM patent attorney A.J. Etienne sought Atanasoff's help in breaking an Eckert-Mauchly patent on a revolving magnetic memory drum, having been alerted by Clifford Berry that the ABC's revolving capacitor memory drum may have constituted prior art. Atansoff agreed to assist the attorney, but IBM ultimately entered a patent-sharing agreement with Sperry Rand, the owners of the Eckert-Mauchly memory patent, and the case was dropped.
On May 26, 1967, computer manufacturer Honeywell Inc. filed a lawsuit against Sperry Rand in U.S. District Court in Minneapolis, Minnesota challenging the validity of the ENIAC patent. The trial, one of the longest and most expensive in the federal courts to that time, began on June 1, 1971, lasted until March 13, 1972, had 77 witnesses, plus 80 depositions and 30,000 exhibits. Atanasoff's machine was introduced as prior art.
The case was legally resolved on October 19, 1973 when U.S. District Judge Earl R. Larson held the ENIAC patent invalid, ruling that the ENIAC derived many basic ideas from the Atanasoff-Berry Computer. Judge Larson explicitly stated, "Eckert and Mauchly did not themselves first invent the automatic electronic digital computer, but instead derived that subject matter from one Dr. John Vincent Atanasoff".
Sperry declined to appeal the decision in Honeywell v. Sperry Rand, but the decision received little publicity at the time, perhaps because it was overshadowed by the Watergate era "Saturday Night Massacre" firing of special prosecutor Archibald Cox by President Richard Nixon the next day. Despite the legal decision, some computer history publications continued to represent the ENIAC, rather than the ABC, as the first electronic digital computer.
In 1961 Atanasoff started another company, Cybernetics Incorporated. He was gradually drawn into the legal disputes being contested by the fast growing computer companies Honeywell and Sperry Rand. Following the resolution of Honeywell v. Sperry Rand, which named Atanasoff the inventor of the automatic electronic digital computer, Atanasoff was warmly honored by Iowa State College, which had since become Iowa State University, and more awards followed. He retired in Maryland and died in 1995 of a stroke after a lengthy illness.
Atanasoff's first national award for scientific achievements was the Order of Saints Cyril and Methodius, First Class, Bulgaria's highest scientific honor bestowed to him in 1970, before the 1973 court ruling.
Other distinctions awarded to Atanasoff include: