Guess where Star Wars makes real money: Not in the theaters

The sales are strong with this one.

Fans and investors alike are celebrating Star Wars Day on Monday, and May the Fourth be with you. This year's celebration holds special significance, ahead of the latest movie in the Star Wars saga and the first to be released in the popular franchise since Disney purchased Lucasfilm in 2012.

When "Star Wars: The Force Awakens" is released in December, it won't just mark the return of Star Wars veterans Harrison Ford, Carrie Fisher and Mark Hamill. The movie will also kick off a new bonanza in merchandising—the real money-maker in the Star Wars business.

Since the first movie came out in 1977, toy licensing alone has brought in about $12 billion in revenue, compared with only $4 billion in box office revenue from the first seven movies. Of course, hit movies are a crucial driver of toy sales, and license deals can make or break a toymaker. (Tweet this)

Disney announced a new generation of Star Wars toys, books and clothing yesterday that the company said will "land in our galaxy" in September. Electronic Arts, which holds an exclusive Star Wars video game license until 2023, is releasing a new Star Wars game a month before the movie premiere.

Disney bought Lucasfilm and the rights to Star Wars for $4 billion in October, 2012, a deal that will likely pay off with this movie and several other sequels and spinoffs in the works, Disney CEO Bob Iger told CNBC last month. Disney made a record $49 billion in revenue last year.

"This is likely to be one of if not our most valuable property once the movie comes out," Iger said.