Frank O'Loughlin was an American League umpire from 1902-1918. He called six no hitters throughout his career. His first and second games were both in 1905 within 45 days of each other. He followed up with one game each in 1908, 1911, 1912, and 1917 for a total of six; the most no hitters called by an umpire since 1901.
Both William Dinneen and William Klem called five no hitters each. Dinneen was an American League umpire from 1909-1937. His first no hit game was in 1910 followed by one game in 1912, one game in 1918, and two in 1923. Klem, a National League umpire from 1905-1941, called his first in 1907, then one each in 1912, 1915, 1916, and his last in 1934.
Out of the 122 umpires who have been behind the plate for a no hitter or perfect game, many of them have done so on more than one occasion. Since 1901, eight umpires have called four games throughout their careers, nine umpires have called three games, and 27 umpires have called two games. Eight out of these 44 umpires who have called multiple games, have done so at both a no hitter and a perfect game.
Bill Dinneen is the only Major League umpire who also pitched a no hitter. Dinneen was behind homeplate for 5 no hitters between 1910 and 1923. He threw his for the Boston Red Sox on September 27, 1905.
Ed and Paul Runge are the only father-son pair to umpire no hitters. Ed worked behind the plate for Dave Morehead's feat on September 16, 1965. Paul umpired for Charlie Lea on May 10, 1981.
Ed Vargo, a National League umpire from 1960-1983, is the only Major League umpire to call one no hitter and one perfect game for the same pitcher. Vargo was behind home plate for Sandy Koufax's no hitter on June 4, 1964 and his perfect game on September 9, 1965.
Five umpires since 1901 have umpired two no hitters in the same season. Thomas Connolly was behind homeplate for Addie Joss' perfect game and Bob Rhoads' no hitter in 1908. Harry Schwarts called two no hitters in 1962 as did Johnny Stevens in 1967, Larry Napp in 1970 and Drew Coble in 1990.
Frank Dwyer called the first American League perfect game by Cy Young in 1904.
Richard Nallin was the first umpire of the twentieth century to call two no hitter's back to back. First on May 5, 1917 he called Ernie Koob's game and then on May 6, 1917 was behind the plate for Bob Groom's. Anthony Venzon also umpired two no hitter's two days in a row. On April 30, 1969 Venzon called Jim Maloney's game and on May 1, 1969, Don Wilson's. William Dinneen called two no hitters within three days. He umpired Sam Jones' on September 4, 1923 and Howard Ehmke on September 7, 1923. William Deegan called two games within 16 days of each other in 1977.
William Klem umpired five no hitters in during his career. His first was on September 20, 1907. 27 years and one day later on September 21, 1934 he called his last making him the umpire with the longest gap between his first and last homeplate appearances.
Joe Brinkman has umpired two no hitters since his start in 1973. His first was on June 19, 1974 and his other on May 12, 2001. This almost 27 year difference is the longest break between two no hitters by the same homeplate umpire since 1901.