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Anatomy of a rumor: Apple’s Sept. 9 event

If you're like me, you've probably read a lot of stories about what Apple will or won't announce on Sept. 9.

I've seen 135 stories about the date on Techmeme alone.

But when I try to I trace the Sept. 9 meme back to its source, I find only three reporters who claim any first-hand knowledge. And one of them -- Daring Fireball's John Gruber -- now says his post was just a joke.

Judging from the buzz on Techmeme, it seems to matter less what Gruber or 9to5Mac's Mark Gurman say. When re/Code's John Paczkowski reports that Apple is going to reveal something on such and such a date, the rest of the press climbs on board.

Three weeks ago it was a large-screen iPhone. This week it's a "wearable."

We'll find out soon enough.

Follow Philip Elmer-DeWitt on Twitter at @philiped. Read his Apple (aapl) coverage at fortune.com/ped or subscribe via his RSS feed.

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