NOTE: This article is not a meme. It describes an observed effect related to Internet memes and pop culture.

The Seinfeld Effect is a phenomenon closely related to the Family Guy Effect (the idea that when a meme is referenced on a popular television show, it dies out). The Seinfeld Effect occurs when a TV show references an in-joke belonging to a subculture (in most modern cases, the Internet) and makes it mainstream, causing the show's viewership to mistakenly believe the meme originated with that show.

The effect is named after the 1989-1998 sitcom Seinfeld's habit of referencing little-known ideas, jokes, and phrases, such as "Festivus," "yada yada yada," or "not that there's anything wrong with that," and making them extremely well-known through the show's populararity to the point that many have the misconception Seinfeld invented these phrases (for the purposes of this article, 1992 is listed as the meme origin date, as that was when the episode "The Contest" popularized the idea of masturbatory celebacy contests).

In the modern day, Family Guy is often the show that is mistakenly believed to have invented memes like Rick-Rolling, Chuck Norris jokes, and Peanut Butter Jelly Time.

The Seinfeld Effect can be frustrating for those who actually did invent the meme, as they receive no credit or recognition. In many cases, this becomes coupled with the Family Guy Effect, where the meme dies because of its pop culture overexposure. In other cases, a news program may attempt to clear up the discrepancy by noting the real origin of the meme--causing an influx of new arrivals to forums like 4chan.