Google's Larry Page tops Fortune's 40 under 40 list

Tech industry leaders dominated this year's Fortune 40 under 40, nabbing the top five spots and then some.

Google's Larry Page came in at No. 1, with the magazine citing the 39-year-old's guidance in a $12.5-billion acquisition of Motorola, closing some of Google's failed projects, and leading the company to an all-time-high stock price.

Page bumped Facebook's Mark Zuckerberg down to No. 2 after the boy genius topped last year's list. Still, Zuckerberg, 28, was no slouch -- he helped the social network hit a billion users and 1.13 trillion "Likes."

Yahoo's new chief Marissa Mayer, 37, came in at No. 3, followed by Google's Sergey Brin, 39, and Twitter's Jack Dorsey, 35.

Other tech giants on this year's list include Salar Kamangar, senior vice president of YouTube and video at Google, at No. 15; Airbnb CEO Brian Chesky at No. 17; and Pinterest CEO Ben Silbermann and Instagram CEO Kevin Systrom in a two-way tie for No. 18.

Honors for the youngest entry on the list this year go to Ashley and Mary-Kate Olson, both of whom are 26.

The list recognizes the best leaders in business.