J. Presper Eckert (at right in the picture on this slide) and John Mauchly were professors in the Moore School of Engineering at the University of Pennsylvania.  Mauchly invited himself to Atanasoff’s home for a long weekend in order to check our the ABC.  Atanasoff made him welcome, showed him his machine, and gave him a copy of the paper describing the workings of the machine that already had been filed with the Iowa State College’s patent lawyer.  Mauchly returned to Pennsylvania and, together with Eckert, designed and built the ENIAC (Electronic Numerical Integrator and Computer) which was commissioned by the U.S. Department of Defense and delivered in 1946.

Eckert and Mauchly successfully filed for the patent as inventors of the electronic digital computer, ignoring Atanasoff’s work.  Some thirty years later, in 1972, this injustice was rectified when Honeywell (for Atanasoff) successfully challenged Sperry Rand (the company that acquired Eckert and Mauchly’s patent), and Atanasoff and Berry were duly credited as being the inventors of the electronic digital computer.

Mauchly died in 1980.  Eckert died in 1995, one week before the nonogenarian Atanasoff.  You might say that Atanasoff had the last laugh.