A 1938 comic book featuring the debut of Superman that was discovered in the wall of an abandoned house could set a new auction record.
Action Comics #1 was found packed into the insulation of a house in Minnesota.
Vincent Zurzolo, who is the chief operating officer of ComicConnect.com, says it has already attracted 35 bids and is likely to exceed its estimated value of $US150,000.
However, he says it could have been worth a lot more if its back cover hadn't been torn in an argument between the man who discovered it and his wife's relatives.
The BBC reports the most expensive Action #1 comic ever sold had a grade of nine and fetched more than $2.1m.
David Gonzales purchased an abandoned house that he planned to renovate and live in with his four children, Mr Zurzolo said.
While tearing down a wall, Mr Gonzales found newspapers from the 1930s used as insulation. Then he came across the comic.
Bidding continues on ComicConnect.com until 11 June.
