Why is anti-piracy software Denuvo stirring controversy?

For video game companies and enthusiasts of legal games, this doesn’t sound too bad. The problem is that Denuvo has previously been accused of causing performance issues on some popular video games, such as Sonic Mania and Tekken 7, with Japanese developer and publisher Capcom even retiring it from its titles Devil May Cry V and Resident Evil 2 (2019) to improve performance.

What exactly is Denuvo?

Denuvo was originally developed by Austrian software company Denuvo Software Solutions GmbH in 2014, which was acquired by software giant Irdeto in 2018. 

Although it is often labeled as a Digital Rights Management (DRM) solution in the media (and it does require an existing DRM system to be fully effective), Denuvo is, in fact, an anti-tamper software.

DRM technologies are meant to control and manage access to digital content, protecting the intellectual property rights of content creators and publishers by preventing unauthorized copying, distribution, and sharing of digital products.

When you buy software and it comes with an activation key, or requires online authentication or an internet connection to be used — that is DRM. Video game developers employ these and other DRM strategies to ensure that only people who buy their games legally can play them. 

Anti-tamper software, on the other hand, tries to prevent tampering by making it harder to reverse engineer its code. In the case of Denuvo, it uses obfuscation techniques to obscure the logic and structure of the game’s code, but also detects when somebody is trying to find bugs in the DRM and initiates countermeasures to stop this. 

Although the company does not clarify its methods, one way to stop an unauthorized debugging attempt is by executing code paths that are meant to confuse debugging tools or that lead to incorrect or irrelevant results.

Moreover, Denuvo encrypts core files of the games, so that if hackers manage to extract them, they can’t access them without the proper decryption mechanism, which is held by the company.

Other sources indicate that Denuvo makes the games run on virtual machines, which are controlled and isolated environments that create a barrier between the game’s code and the hardware of the player’s computer as the game is running. This is called virtualization, but it is more related to the firm’s anti-cheat solution than its anti-tamper solution.  

Does Denuvo affect performance?

According to Irdeto, Denuvo is integrated into the game build toolchain.

In game development, a "build" refers to a compiled version of the game's code, assets, and resources which is ready for distribution or testing, while the "toolchain" is the set of software tools used to build the game. 

This means that Denuvo’s anti-piracy mechanisms are applied to the code of a game during the development stage, adding layers of complexity which can make the code harder to execute, process, and/or optimize.

As a result, Denuvo’s protection measures could increase the workload on the CPU and result in frame rate drops, longer load times, or other performance issues. Denuvo could also contribute to higher memory usage, as the game needs to allocate resources for both the game itself and the anti-piracy mechanisms. 

Furthermore, integrating anti-piracy measures deeply into the game's code may lead to compatibility issues with specific hardware configurations.

Does it cripple performance?

So, if it’s so bad, and if some reputable video game studios have removed it from their products, why did Nintendo choose to add Denuvo’s anti-piracy mechanisms to Switch games?

One thing to consider is that game development is a complex process with many elements, and any of them can contribute to performance issues, not only the implementation of anti-piracy protection methods. Think of the game engine itself, the optimization of the game’s codes and graphics, hardware and driver compatibility, etc.

For example, the Nintendo Switch has specific hardware limitations in terms of its CPU, GPU, and memory—just like PCs. If a game's requirements exceed what the Switch can handle, or if it’s simply not properly optimized for that console, it might lead to performance issues, regardless of Denuvo. Background apps, outdated firmware, inadequate settings, etc., can also impact game performance on Switch. 

For this reason, gamers shouldn't automatically blame Denuvo if the game does not run as expected. While there are cases in which removing Denuvo enhanced game performance, there are also cases in which removing Denuvo did not change game performance at all. 

Denuvo’s owner Irdeto is not very talkative, but the company's Chief Operating Officer of Video Games Steeve Huin denied the accusations earlier this year. As might be expected, Huin said that Irdeto always verifies that there is no perceptible impact on game performance due to its anti-tamper protection. 

Huin also said that people who analyze the performance of games with and without Denuvo on forums, YouTube channels, etc.,  often overlook other changes that games can go through from the date of release to the date of removal of Denuvo, such as bug fixes or updates. 

But he signalled that he is also aware of the product’s bad reputation and is aware that there is a sense of mistrust regarding Denuvo among some gamers.

"In the pirating/cracking community, we're seen as evil because we're helping DRM exist and we're ensuring people make money out of games," Huin told Ars Technica.

Regardless of the perceived and actual effects, the product has been successfully applied to many AAA games without any effect on their performance, and is now the heart of the Nintendo Switch Emulator Protection project.