Rovio has signed a six-year exclusive deal to make mobile games using the Moomin characters.
It also has the rights to make games using Moomins on any gaming platform. After the first six-year agreement has expired, the agreement has a possible extension for another six-year period.
As part of the deal, Rovio has also taken a small investment in Gutsy Animations, the creator of the Moominvalley 3D animation series.
Rovio has taken a €2.5 million ($3 million) equity stake in Gutsy, plus a similarly-valued convertible loan.
"Gutsy Animations did an astonishing job at bringing to life the rich stories and alluring atmosphere of the Moominvalley," commented Rovio CEO Alex Pelletier-Normand.
"Working with Gutsy and Moomin will give us the opportunity to present this iconic brand to new audiences across the globe at the same time as we surely will delight our existing fans. This partnership will diversify our IP portfolio, which is a key step in our consistent growth strategy.
"Rovio’s first Moomin game, based on the original story and world created by Tove Jansson and inspired by the Moominvalley visuals, is already being developed and we expect it to reach soft launch later this year."
Moomin characters managing director Roleff Kråkström added: "This partnership marks an important milestone in our strategy to take local Nordic creations to the international marketplace."
Rovio recently teamed up with Burger King to offer Angry Birds plushies and an AR game.
The studio also promoted its vice president of marketing Kieran O'Leary to chief operating officer.