What this post is about
- GNU General Public License (GPL)
- Apache License
- Mozilla Public License (MPL)
- MIT License
- And the right license for you?
The open-source community is a space in which creative IT development and collaborative work are defining elements. Everyone contributes, designing their own requirements as they see fit.
Despite the freedom developers have to implement their ideas, the foundation of all open-source projects is an appropriate license with obligations and rights. This gives contributors the permission, within the scope of the respective license, to advance and potentially distribute the software.
Our review of the five important licenses explains the striking differences.
The GNU General Public License (GPL) is the most widely used license in the open-source segment. The GPL guarantees that software based on an operating system remains freely accessible and free of charge at all times and at every stage of development. In doing so, it fully reflects the communal nature and the founding principles of open source.
However, developers should be cautious: by using the GPL, they commit to distributing their software based on this license without additional costs to users. Distribution for financial gain is thus excluded!
The GPL enforces a strict copyleft, ensuring that all enhancements and modifications are also made available under the GPL. In the open-source world, copyleft describes the condition under which the original license must be maintained, if at all.
This is the antithesis to the GPL. The BSD License (short for Berkeley Software Distribution License) is a non-copyleft license that allows for commercial distribution.
Software developers are permitted to commercially offer their own created programs, thereby generating revenue through sales. They are not even required to disclose access to the source code.
In this way, an original open-source project can gradually evolve into a closed system, largely disregarding the fundamental principles. BSD licenses should therefore only be used when the goal is the active distribution of software that is intended to be developed internally only.
Another non-copyleft license is the Apache License. When using this license, programmed tools and software may also be commercially distributed. However, unlike the BSD License, changes or modifications to the source code must be documented and made clear.
With this requirement, at least a small amount of respect is shown for the open-source character. Authors and contributors who participated in the original code thus receive minimal credit. If further changes are made to the final work created under the Apache License, they may potentially be carried out under a different license.
For developers grappling with decision-making, the Mozilla Public License (MPL) is a suitable option. It features a limited copyleft, allowing developers to make a decision during the development of their project.
If the original code is used without modifications, it is mandatory to provide the software for free. However, if the planned ideas require adaptation and variation of the code, this obligation is waived. Selling the modified software as a commercial product is thus allowed.
The license from the Massachusetts Institute of Technology is among the most widely used licenses, alongside the GPL. All modifications and actions made to the software require that the software is ultimately made freely available. Additionally, license texts and copyright notices must be distributed along with the software.
In principle, the MIT License is very broadly formulated, offering the best option to freely distribute or commercially offer software, as only credits need to be made visible.
Choosing the right license depends significantly on your goals post-development. If you want to support the open-source community and contribute to a free world, opting for licenses with clear copyleft provisions is advisable. If the desire to distribute your tools with restricted reuse predominates, opting for a non-copyleft license is recommended.
Additional assistance is available through platforms such as ChooseALicense.com or the OSCAd Framework (short for "Open Source Compliance Advisor") for selecting and adhering to the diverse requirements of licenses.
Make thoughtful decisions before starting development! Take the time to carefully evaluate your project, as the presented licenses come with varying conditions and implications for the use and distribution of open-source software. Choosing the right license depends on your organization's goals and developers, whether you aim to support the open-source community or distribute your software with limited reuse.