New Japanese banknotes that were put into circulation a month ago have been increasingly listed on online auction sites, and a new ¥10,000 note with the same numbers in its serial number sold for as high as ¥70,000.
Bids surpassing a banknotes face value have also been observed for new ¥1,000 notes.
Circulated notes can be listed on Yahoo Auction as long as their collectible or scarcity appeal is recognized.
"There is a certain level of demand" for circulated bank notes, said an official at LY, the operator of the auction site.
However, banknotes could be removed from the site if they lack collectible value.
No listing of new banknotes has been confirmed on popular flea market app Mercari as its operator bans banknotes and cash vouchers from being listed.
There are concerns that the app will be used to launder money, a Mercari official said. If banknotes are listed, they could be removed, the official said.