Did Led Zeppelin Filch the Opening Notes of 'Stairway to Heaven' from Relatively Forgotten California Band?

Posted the song here, "'Stairway to Heaven'."

And here's Business Week, "Stairway to Heaven: The Song Remains Pretty Similar":

Weary from touring, Led Zeppelin guitarist Jimmy Page retreated in 1970 to a stone cottage in Wales, called Bron-Yr-Aur, with no power or running water. Legend has it King Arthur fought his last battle nearby. Not far off is the mountain Cader Idris where, it’s said, those who spend a night at its summit are fated to die, go mad, or become poets. At Bron-Yr-Aur, by candlelight, Page constructed the bones of what may well be the most popular, and valuable, rock ’n’ roll song of all time, Stairway to Heaven. This included the introductory finger-picked section that launched a million guitar lessons.

Back in England that winter, Page laid out the budding epic for the band at another house, Headley Grange, where the magic continued around a fire fueled on one occasion by a section of stairway banister. As Page plucked, singer Robert Plant seemed to channel another world as he wrote the lyrics. To Page, who has referred to the song as “my baby,” it was Zeppelin’s crowning achievement. “Stairway crystallized the essence of the band,” he told then-teenage rock writer Cameron Crowe in a March 13, 1975, Rolling Stone interview. “It was a milestone for us. Every musician wants to do something of lasting quality, something which will hold up for a long time, and I guess we did it with Stairway.”

For generations of middle-class youth, the song is the 8-minute soundtrack of adolescent romance—or at least the anticipation of it. Stairway is slow dancing, the last song played at high school proms, sweet-16 parties, and summer camp mixers across a broad swath of the late 20th century.

Stairway’s stature—financially, culturally, and musically—is towering. By 2008, when Conde Nast Portfolio magazine published an estimate that included royalties and record sales, the song had earned at least $562 million. It was so profitable in part because Led Zeppelin refused to release the song as a single, forcing fans to shell out for the entire album, which is untitled but known as Led Zeppelin IV. In the U.S., the album has sold more copies (23 million, according to the Recording Industry Association of America) than any save Michael Jackson’s Thriller and the Eagles’ Their Greatest Hits (1971-75). To this day, Warner Music Group cites the song in its annual reports as an example of its publishing portfolio.

For live audiences, Stairway’s power starts with its introductory notes. “Can you think of another song, any song, for which, when its first chord is played, an entire audience of 20,000 rise spontaneously to their feet, not just to cheer or clap hands, but in acknowledgment of an event that is crucial for all of them?” Observer critic Tony Palmer wrote in a 1975 profile. Dave Lewis writes in Led Zeppelin: The Complete Guide to Their Music that “Stairway has a pastoral opening cadence that is classical in feel and which has ensured its immortality.”

But what if those opening notes weren’t actually written by Jimmy Page or any member of Led Zeppelin? What if the foundation of the band’s immortality had been lifted from another song by a relatively forgotten California band?

You’d need to rewrite the history of rock ’n’ roll...

Yeah, well, a little late now, don't you think?

But keep reading, in any case.