The release of Pokémon Go has been a phenomenon on a scale very rarely seen in gaming and the financial markets have taken notice. Nintendo stock (which trades as NTDOY in the U.S.) is up well over 50 percent since the game came out, its biggest upward move since the high-flying Wii days. That adds around $12 billion dollars to the company’s market capitalization, according to the Wall Street Journal. That’s truly huge. But, if you really dig down, it may actually be way overblown… because Nintendo’s just got a tiny sliver of that Pokémon Go money coming its way.

Why The Surge In Nintendo Stock Is A Little Questionable

Here’s the thing: Nintendo doesn’t own all of Pokémon Go. Let’s break it down. Pokémon Go was developed by Niantic and published by The Pokémon Company. The Pokémon Company is a joint venture between Game Freak, Creatures Inc. and Nintendo. Nintendo owns a one-third share of The Pokémon Company. According to MarketWatch, the company also owns 10 percent of creatures. It’s getting complicated, huh? Well, Nintendo also owns a big chunk of Niantic itself, although it’s not clear quite how much.

So when it comes down to actual revenues from Pokémon Go, the pie is split into many slices. Apple and Google get a 30-percent share, as is their standard cut for in-app purchases on iPhone and Android. Niantic gets a piece, some of which goes to Nintendo. So does The Pokémon Company, and a portion of that piece also ends up going to Nintendo. As WSJ notes, the exact proportions, the exact amount of money Nintendo can make from Pokémon Go, can’t be calculated with the information we have.

Estimates for Pokémon Go’s revenue vary widely, from a little less than a million a day to $1.6 million. Best case, that’s around $600 million a year, only some of which goes to Nintendo. Does that translate to a $12 billion increase in market capitalization? Hard to say. There are other major factors involved. Nintendo itself is introducing the Pokémon Go Plus device, which will drive additional revenue. Niantic’s sponsored PokéStops and gyms will bring in even more money, and the game has yet to even launch in most of the world. Plus there’s talk of a movie. Beyond that, the game’s success bodes well for Nintendo’s future smartphone apps—and surely that’s what investors are hoping for. But as of right now, the contribution Pokémon Go is making to Nintendo’s bottom line is far less than the leap in the stock might suggest. That’s okay, though—it’s all about potential.