Marvel Entertainment Inc. said its shareholders would vote Dec. 31 on whether to approve its $4 billion acquisition by Walt Disney Co.

Under the deal, first announced Aug. 31, Disney will pay Marvel shareholders $30 cash and 0.7 shares of Disney stock for every share of Marvel stock.

The acquisition would give Disney access to New York-based Marvel’s stable of popular comic book characters, which include Spider-Man, the X-Men and Iron Man, once licenses with other companies expire. It’s Disney’s largest deal since 2006, when the Burbank entertainment giant bought Pixar Animation Studios Inc. for $7.4 billion in stock.

The deal is expected to close upon approval and turn Marvel into a wholly-owned subsidiary of Disney, Marvel said.