Larry David's guiding principle was that the best material came from real life — from the specific, observed details of actual experience rather than invented scenarios. Over nine seasons, the show drew directly from events in David's life, Jerry Seinfeld's life, and the lives of the writing staff.
Here is the full list of episodes with documented real-life origins.
The bet on who can go longest without self-gratification was based on a real contest Larry David had with his friends. David won. The decision to put it on national television, circumnavigating the subject through euphemism, was his most audacious autobiographical move.
The storyline in which Jerry and George pitch a show about nothing to NBC is based directly on the real pitch that Seinfeld and Larry David made to NBC in 1988. The real pitch succeeded. The show's fictional version fails. This is the show at its most self-aware.
George quitting his job and trying to return as if nothing happened was based on an incident in Larry David's career at Saturday Night Live. He quit in a rage, returned the following week, and discovered that no one was going to acknowledge what had happened.
Based on Al Yeganeh and the real Soup Kitchen International, whose ordering protocol was genuine. Writer Spike Feresten experienced the real ordering system and recognised it as comedy.
Based on a real holiday invented by Dan O'Keefe's father in 1966. O'Keefe pitched it to the writers. The show changed many of the original customs, but the basic structure was real. The O'Keefe family celebrates Festivus to this day.
Based on Larry David's actual experience of waiting for a table and deciding the experience itself was sufficient material for an episode. The NBC executives were skeptical: nothing happens in this episode, they said. Exactly, said David.
The parking garage episode was drawn from universal experience — every writer on the show had experienced some version of it. The Marine Biologist premise was drawn from real experiences of people maintaining social fictions. The Junior Mint came from a half-serious writers' room discussion about antibacterial properties.
The Pilot storyline mirrors the real Seinfeld creation process. The Pen — social pressure to accept gifts in retirement communities — was drawn from direct observation. The Handicap Spot — parking illegally and facing consequences — was based on a real incident involving someone connected to the writers' room.