This photo provided by Heritage Auctions shows a copy of Action Comics No. 1, the comic book that introduced Superman to the world in 1938, which sold for $6 million on Thursday, April 4, 2024. (Heritage Auctions via AP)

NEW YORK (AP) — A 1938 copy of the comic book that first “introduced Superman to the world” has sold for a record-setting $6 million, the auctioneer that handled the purchase said last week.

According to Heritage Auctions, the rare copy of Action Comics No. 1 was sold to an anonymous buyer on Thursday.

The $6 million price tag makes the book the most expensive comic to ever sell at auction, the action house added.

Heritage Auctions hails Action Comics No. 1 as “the most important comic ever published” — noting that the Superman who first appeared in the 1938 spring issue “remains remarkably like” the version still seen in comic strips and on the big screen today.

A report from comic book grading service Certified Guaranty Company, cited by Heritage Auctions, estimates that there are only 100 surviving copies of Action Comics No. 1 today — out of 200,000 that were printed by National Allied Publications, the predecessor to DC Comics.

The copy sold last week, which comes from the Kansas City Pedigree, has a “Very Fine+” CGC rating of 8.5 — with only two other unrestored issues of grading higher, Heritage Auctions noted.

Although not as high as $6 million, other rare copies of Action Comics No. 1 have also gone for millions at auction in recent years, including a 6.0-rated issue that sold for $3.56 million through ComicConnect last year.

Thursday’s record sale surpasses the previous titleholder of the most expensive comic book to ever be sold — which was a copy of another Superman-starring comic, Superman No. 1, that sold privately for $5.3 million in 2022, according to CGC.

The Action Comics No. 1 sale was part of a four-day comic auction event that featured several big-name superheroes and rare comics featuring them. The event realized more than $28 million by its end.