Nintendo Co., LTD. filed an application on Thursday with the United States Patent & Trademark Office for “Hand-Held Video Game Platform Emulation.”

The patent would cover the use of video game software from the Nintendo Game Boy “on a low-capability target platform,” meaning smartphones, PDAs, and other devices not made by Nintendo.

Emulators allow software such as video games to be run on devices for which they were not originally intended. A popular tool called DOSBox, for example, allows old MS DOS games to run on modern Windows systems.

At face value, the application might make it seem like Nintendo intends to re-release old Game Boy games like Super Mario Land on modern smartphones, much like Square Enix did with the earlier Final Fantasy games.

But with Nintendo still selling old titles through their proprietary systems like the Wii U, the patent likely has another purpose – putting a stop to third party emulators.

A legal gray area

Third party emulators of proprietary systems are not strictly illegal in the US. In the case of Sega v. Accolade, for example, the court determined Accolade Inc.’s reverse engineering of the Sega Genesis to create unlicensed games fell under fair use.

The case set a precedent that would later be used in the similar case of Sony Computer Entertainment, Inc. v. Connectix Corporation, which determined that a PlayStation emulator created by reverse engineering the game system did not infringe on Sony’s copyrights.

As a result, the basic functionality of computer software is not protected by copyright laws, and instead can only be protected by trade secrets and patents. Patents like the one Nintendo just filed.

Could it be good news for gamers?

While Nintendo’s patent might be thinking of the company’s intellectual property first, that is not to say that the gaming giant will never venture into the world of mobile games.

Earlier this year, Forbes contributor Eric Kain wrote: “Nintendo could keep exciting new IPs on proprietary hardware exclusively, while still getting Mario into the hands of millions of smartphone and tablet users, like some sort of beneficent gateway drug.”

With the wealth of side-scrolling indie games that try to recapture that mid-1990s feeling, releasing old games on smartphones could be good business for Nintendo.