GPLv2 vs. MPL v2

Attribute	GPLv2	MPL v2
License Type	Copyleft	Weak Copyleft
Compatibility with other licenses	Less compatible	More compatible
Derived works	Must be under GPLv2	Can be under different license
Patent Grant	No explicit patent grant	Explicit patent grant

Introduction

Open source licenses play a crucial role in governing the use, modification, and distribution of software. Two popular open source licenses are the GNU General Public License version 2 (GPLv2) and the Mozilla Public License version 2 (MPL v2). While both licenses are designed to promote the sharing and collaboration of software, they have distinct attributes that developers and organizations need to consider when choosing a license for their projects.

Scope of Application

One key difference between GPLv2 and MPL v2 lies in their scope of application. GPLv2 is a copyleft license, which means that any derivative works of software licensed under GPLv2 must also be released under the same license. This ensures that the source code remains open and freely available to the community. On the other hand, MPL v2 is a weak copyleft license, allowing developers to combine MPL-licensed code with proprietary code without requiring the proprietary code to be open-sourced.

Compatibility

Another important consideration when choosing a license is compatibility with other licenses. GPLv2 is known for its strict copyleft provisions, which can make it incompatible with certain proprietary licenses. This can limit the ability of developers to combine GPLv2-licensed code with proprietary code in a single project. In contrast, MPL v2 is designed to be more permissive and is compatible with a wider range of licenses, making it easier for developers to incorporate MPL-licensed code into their projects.

Modifications and Derivatives

When it comes to modifications and derivatives, GPLv2 and MPL v2 have different requirements. Under GPLv2, any modifications or derivatives of the licensed software must be released under the same license, ensuring that the source code remains open and accessible. This can be a significant consideration for developers who want to contribute back to the open source community. In contrast, MPL v2 allows developers to create modifications and derivatives without being bound by the same license, providing more flexibility in how the code is used and distributed.

Attribution and Notices

Both GPLv2 and MPL v2 require developers to include certain attribution and notice requirements when distributing software under these licenses. However, the specifics of these requirements differ between the two licenses. GPLv2 requires that all copies of the software include a copy of the license and copyright notices, ensuring that users are aware of their rights and obligations under the license. On the other hand, MPL v2 requires developers to include a notice in the source code files that have been modified, indicating the changes that have been made to the original code.

Enforcement and Compliance

Enforcement and compliance with open source licenses are essential to ensuring that the principles of open source software are upheld. GPLv2 is known for its strong enforcement mechanisms, including the ability to take legal action against violators of the license terms. This can provide developers with a sense of security knowing that their code will be protected. In comparison, MPL v2 relies more on community enforcement and encourages collaboration to resolve any compliance issues that may arise.

Conclusion

In conclusion, both GPLv2 and MPL v2 are popular open source licenses that offer unique benefits and considerations for developers and organizations. While GPLv2 is a strict copyleft license that promotes the sharing and collaboration of software, MPL v2 provides more flexibility and compatibility with other licenses. Ultimately, the choice between GPLv2 and MPL v2 will depend on the specific needs and goals of the project, as well as the desired level of openness and collaboration within the development community.