With the exception of an auction held in the 1980s to raise funds for Yoko Ono's Spirit Foundation charity, Yoko Ono rarely, if ever, sells off any of John's personal posessions (and has never sold off any of John's handwritten lyric sheets).
The John Lennon handwritten lyric sheets that occasionally come up for sale at auction are items that John left behind in the studio, or otherwise discarded or abandoned in hotel rooms, etc. There was little thought that such items had any value back then -- and so they were often simply abandoned or thrown out. Studio employees, musicians, hotel employees and others would find them and keep them. Later, these items would be put up for auction, many of them changing hands through collectors over the years as prices rose.
Yoko also does not sell off any of Lennon's original artwork. John Lennon released a series of signed lithographs (mostly of his nude drawings of Yoko) that occasionally come up for sale -- but all of his other "artwork" that is being sold today are reprints produced by Yoko -- not the original artwork.
Yoko Ono has carefully collected and archived Lennon's personal artifacts, and occasionally has lent some of these items to museums so that Lennon fans around the world get a chance to see them.
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england
I was !
john Lennon
Japan
alfred
poopy dunk
No.
the Dakota in NYC
No
No he was not
Imagine.