Originally Posted by
ngroove
1963 - 1964 - Amazing Spider-Man #3 - Annual #1 (around between issues #15 and #16 time) - Doctor Octopus.
1964 - 1966 - Amazing Spider-Man #17 - 40 - Green Goblin / Norman Osborn.
1966 - 1970 - Amazing Spider-Man Issues #41 - 49 each had turns of guys Spidey either put away or cured, then from issue #50 through #85, it was Kingpin.
1970 - 1973 - Anybody's guess. Green Goblin had a couple notable returns in notable stories, drug issues and Gwendolyn Stacy's death, but he's been thought cured / dead on those. Doctor Octopus did not really attempted to murder George Stacy - he threw himself at the way of the kid, and Spidey's tentacle-control jamming formula web jammed at Otto's control over his tentacles. Octopus also was notable for "courting" Aunt May at the period, May agreeing to be under the protection of Otto and / or his men, under the assumption that he's a good man, while the bigger threat of those tales, 1972 - 1976, was Hammerhead, Octopus' gang war mob boss rival of the period.
1974 - 1975 - Amazing Spider-Man #129 - 149 - Jackal, Clone Saga #1.
1976 - 1983 - Notable masterminds of period: Kingpin, of Amazing Spider-Man #154, #163 - 164, 195 - 197; Lightmaster, of Peter Parker, The Spectacular Spider-Man #1-3, #19-20; Green Goblin / Doctor Barton Hamilton, of Amazing Spider-Man #175 - 180; Professor Spencer Smythe, behind the events of Amazing Spider-Man #186 - 192; and Mysterio, of Amazing Spider-Man #193 - 199, Peter Parker, the Spectacular Spider-Man #50-51.
1983 - 1987 - Hobgoblin / Roderick Kingsley, then joint effort, of Hobgoblin / Roderick Kingsley and Rose / Richard Fisk. There was also a significant Doctor Octopus threat, Spectacular Spider-Man #72 - 79, and Kingpin string-pulling the Black Cat, Spectacular Spider-Man #90 - 100.
1988 - 1994 - Spidey's chief nemesis of popular one-dimensional grudge matches and comebacks was Venom, then Carnage. Also of note, Green Goblin / Harry Osborn in Spectacular Spider-Man #178 - 184, #189-190, #199-200, #204, Amazing Spider-Man #369, #389, Doctor Octopus, notably the Sinister Six stories of Amazing Spider-Man #334-339, Spider-Man #18-23, and Spider-Man Unlimited #3, as well as throughout Gerry Conway's run throughout Spectacular / Web of Spider-Man, 1988 - 1990, Tombstone, Hammerhead, Chameleon, Lobo Brothers, and Puma.
1995 - Jackal, Clone Saga #2. Also of runner-up note, Doctor Octopus / Carolyn Trainer.
1996 - Joint effort of Gaunt / Mendel Stromm, and Norman Osborn / Green Goblin.
1997 - 1998 - Norman Osborn / Green Goblin. Others of note, throughout 1996 - 1998, Black Tarantula, and his rivalry against Rose / Jacob Conover and Delilah.
1999 - 2000 - Senator Ward.
2001 - 2007 - Green Goblin / Norman Osborn.
2007 - 2009 - I presume, Mister Negative / Menace / Norman Osborn.
2009 - 2012 - I presume, Doctor Octopus, then Kravens
2013 - present - I presume, Doctor Octopus, then Norman Osborn.