William Murphy in the 1900s
Philip Roemer in the 1920s
Philo Farnsworth in 1927 (-1)
Domenico DeDomenico in 1958
Joseph Friedman in the 1930s (-1, or -3, or -5)
Maurice Kanbar in 1992 (-1)
Don and Doris Fisher in 1969
Gilbert Baker (-7)
Andrew Smith Hallidie in 1873 (-1)
Charles Hall in 1968 (-1)
Frank Epperson in 1905 (-4)
Levi Strauss and Jacob Davis in 1873 (+0, or +2, or +4)
Charles Fey in 1887 (-9)
George Whitney in 1928
Ernst F. Baruth in 1896 (-5)
You can validate your puzzle solution with certitude.