LOS ANGELES - The Walt Disney Co. said Monday it is buying Marvel Entertainment Inc. for US$4 billion in cash and stock, bringing characters like Iron Man and Spider-Man into the family of Mickey Mouse and WALL-E.

Under the deal, Disney will acquire ownership of 5,000 Marvel characters. Many of them, including the Fantastic Four and the X-Men, were co-created by the comic book legend Stan Lee.

Analyst David Joyce of Miller Tabak&Co. said the acquisition will help Disney appeal to young men who have flocked to theatres to see Marvel's superheroes in recent years. That contrasts with Disney's recent successes among young women with such fare as "Hannah Montana" and the Jonas Brothers.

"It helps Disney add exposure to a young male demographic it had sort of lost some balance with," Joyce said, noting the $4 billion offer was at "full price."

Disney said Marvel shareholders will receive $30 per share in cash, plus 0.745 Disney shares for every Marvel share they own. That values each Marvel share at $50 based on Friday's closing stock prices.

Marvel shares jumped $10.17, or 26 per cent, to $48.82 shortly after the market opened. Disney shares fell 47 cents, or 1.8 per cent, to $26.37.

Disney said the boards of both companies have approved the transaction, but it will require an antitrust review and the approval of Marvel shareholders.

Disney CEO Robert Iger said the acquisition combines Marvel's "strong global brand and world-renowned library of characters" with Disney's "unparalleled global portfolio of entertainment properties" and ability to maximize value across multiple platforms and territories.