Minecraft Server Software and Modding Plug-Ins Facing Uncertain Future

The Minecraft community has been on a roller-coaster ride the past few months, driven by complicated and often misunderstood legal issues related to Minecraft software development, including updates to the end-user license agreement (EULA), software licenses and copyright infringement claims (DMCA), and Microsoft's recent acquisition of Minecraft developer Mojang for $2.5 billion.

In June, Mojang published a blog post clarifying the Minecraft EULA when it comes to monetization of Minecraft videos and servers. The company explains in the post that "legally, you are not allowed to make money from our products." However, the company is allowing exceptions to this rule for Minecraft videos and servers per specific monetization guidelines. Reaction from the Minecraft community continues to be mixed, with some defending the EULA update and others very strongly against it.

Minecraft is available on Xbox One, Xbox 360, PlayStation 3 and 4, and PC/Mac. Minecraft Pocket Edition available on iOS and Android. Image credit: Microsoft

Very soon after the original post, Mojang published an additional blog post answering questions about the EULA and reiterating that server owners had to comply with the terms. According to Mojang, the purpose of the updated EULA is to try to prevent Minecraft servers from becoming “pay-to-win.” The Mojang support page states, "The EULA will not be updated with these allowances; instead, they will soon be a part of a larger document, the Commercial Use Guidelines, which defines acceptable commercial use of the Minecraft name, brand and assets, including Minecraft servers."

On Aug. 21, a series of tweets involving several Mojang Minecraft developers and EvilSeph, the team lead for the Bukkit Project at the time, show the first signs of trouble between Mojang and Bukkit. Bukkit is an API and collection of libraries that developers use to create plug-ins that add new features to Minecraft servers. This Twitter conversation inadvertently makes it known that Mojang is the "owner" of Bukkit and had acquired Bukkit several years ago. By the end of the day, Mojang takes ownership of Bukkit, and the company clarifies that EvilSeph did not have the authority to shut down the Bukkit project.

Storify story explaining the Mojang Bukkit Microsoft events in greater detail. View full-page version on the Storify website.

On Sept. 3, Wesley Wolfe (aka Wolvereness), a major CraftBukkit contributor, initiates a DMCA notice against CraftBukkit and other aliases, including Spigot, Cauldron and MCPC-Plus-Legacy. CraftBukkit is a mod for the official Minecraft server that uses the Bukkit API. CraftBukkit and Bukkit are used together by developers to create plug-ins that can add new features to Minecraft servers. CraftBukkit is licensed as LGPL software while Bukkit is licensed as GPLv3. The DMCA notice states:

Mojang has not authorized the inclusion of any of its proprietary Minecraft software (including its Minecraft Server software) within the Bukkit project to be included in or made subject to any GPL or LGPL license, or indeed any other open source license. ... As the Minecraft Server software is included in CraftBukkit, and the original code has not been provided or its use authorized, this is a violation of my copyright. I have a good faith belief the distribution of CraftBukkit includes content of which the distribution is not authorized by the copyright owner, its agent, or the law.

While the DMCA notice is not directed at the Bukkit API itself, the DMCA has essentially rendered the API unusable as it is designed to be used with CraftBukkit, which has been shut down. The files with infringing content as mentioned in the DMCA notice are .jar files that contain decompiled, deobfuscated edited code that was derived from the compiled obfuscated bytecode created by Mojang.

CraftBukkit was issued a DMCA notice on Sept. 3.

Since the shutdown of CraftBukkit and its other aliases, developers have been scrambling to find solutions to the Minecraft server shutdowns. One of the Minecraft server solutions is SpongePowered, a project that combines the strengths of the Minecraft server and modding communities. Sponge is intended to be both a server and client API that allows anyone, particularly server owners, to mod their game. To avoid the recent DMCA problems plaguing Bukkit, CraftBukkit and their aliases, Sponge and SpongeAPITrack this API will be licensed under MIT, without a Contributor License Agreement.

One of the best comments about the DMCA situation posted in the Bukkit forum was written by TheDeamon, who said:

This is basically the long and short of it, Wolvereness has demonstrated in an indisputable way that Craftbukkit was a licensing bomb waiting to go off in any number of ways. The legalities of Bukkit's use of proprietary code from Mojang essentially wasn't the major deciding factor, it was how that code's existence, as proprietary code, interacted with the licensing used for code being used within the project itself.

TheDeamon went on to say:

Any non-Mojang project that tries to assume the mantle of CraftBukkit, or anything else remotely like it for other titles out there, should be taking notes on what went down here, regardless of what any final legal precedents may come from this. Any kind of open-source community driven project needs to make sure that the license their project is using actually is appropriate to what they are doing, or it is going to find itself a likely hostage of lone contributors in their own future.

To complicate matters even further, Microsoft and Mojang announced on Sept. 15 that Microsoft had agreed to purchase Mojang for $2.5 billion. Mojang founders, including Markus Persson (aka Notch), are leaving the company to work on other projects.

The Mojang Bukkit situation involves very complex legal issues, including two separate software acquisitions (Mojang acquiring Bukkit, Microsoft acquiring Mojang), making it very difficult to draw any conclusions as to which parties have the legal winning argument. There are several key questions that this case brings to light:

  • What exactly does Mojang "own" when it comes to Bukkit?
  • Did the Mojang purchase include the Bukkit code, which is licensed under GPLv3?
  • Who is the owner of the decompiled, deobfuscated edited source code from the Minecraft server .jar files?
  • Should decompiled, deobfuscated edited source code be subject to copyright? Under which license?

The Mojang Bukkit situation will most likely be settled by the courts, making this case one that developers and companies in the software industry should pay very close attention to. Clearly Microsoft can afford the legal team necessary to sort out all of these complex issues when it comes to Minecraft software development.

The courts have already rendered a controversial software copyright decision when it comes to APIs. The recent Oracle v. Google API copyright judgment has created a legal precedent that could impact millions of APIs, destabilizing the very foundation of the Internet of Things. As reported by ProgrammableWeb, the court wrote as part of its findings that "the declaring code and the structure, sequence, and organization of the API packages are entitled to copyright protection." In addition, the court said that "because the jury deadlocked on fair use, we remand for further consideration of Google’s fair use defense in light of this decision."

The Oracle v. Google copyright battle is far from over and upcoming years will bring many more court decisions regarding software copyrights. For those in the API industry, particularly API providers, API Commons is a not-for-profit organization launched by 3scale and API evangelist Kin Lane that aims to "provide a simple and transparent mechanism for the copyright-free sharing and collaborative design of API specifications, interfaces and data models."

API Commons advocates the use of Creative Commons licenses such as CC BY-SA or CC0 for API interfaces. Choosing the correct license for your software or your API is extremely important. A software license is what establishes copyright ownership, it is what dictates how the software can be used and distributed, and it is one of the ways to ensure that the terms of the copyright are followed.

The CraftBukkit DMCA notice, regardless of whether it's a legitimate claim or not, has profoundly impacted the Minecraft community, causing the nearly immediate shutdown of thousands of Minecraft servers and leading to an uncertain future for Minecraft server software and modding plug-ins. Imagine if the courts definitely rule that APIs are subject to DMCA copyright protection; just one DMCA notice aimed at an API as popular as Facebook, for example, could disrupt millions of sites and impact millions upon millions of end users. This hypothetical scenario should not be allowed to happen in the future, and the creativity and resourcefulness of the API community is how it won't be.

Janet Wagner is a freelance technical writer and contributor to ProgrammableWeb covering breaking news, in-depth analysis, and product reviews. She specializes in creating well-researched, in-depth content about APIs, machine learning, deep learning, computer vision, analytics, GIS/maps, and other advanced technologies.