Understanding Open Source Licenses: GPL, MIT, Apache Compared

This article does not constitute legal advice and only reflects the author’s personal assessment at the time of publication. For legal advice on licensing issues, please consult an attorney. Open source licenses determine how software may be used, modified, and distributed. The three main types of licenses are GPL (copyleft), MIT (permissive), and Apache (permissive with patent protection). The GPL requires that changes also remain freely available, while MIT and Apache offer more flexibility for commercial use. The right license choice depends on your business goals and legal requirements.

What are open source licenses and why are they important?

Open source licenses are legal agreements that define the terms under which software may be freely used, copied, modified, and distributed. They create legal certainty for developers and users by defining clear rules for dealing with the source code. Without these licenses, the use of third-party software would be legally problematic.

The legal significance of open source licenses is immense: they replace the standard copyright, which prohibits any use, with specific permissions. Companies need to understand these licenses, as violations can lead to costly litigation.

Open source licenses can be divided into two main categories:

• Copyleft licenses (such as the GPL): require changes to be published under the same license
• Permissive licenses (such as MIT, Apache): allow integration into proprietary software without publication obligation

This distinction significantly influences your business strategy and product development. Copyleft licenses promote community development but can restrict commercial models. In the context of copyleft licenses, one often speaks of “infectious” conditions, without negatively connoting this, but simply to point out that works derived from the use of copyleft code are also generally subject to the same license. Permissive licenses offer more flexibility for companies that want to develop proprietary solutions.

What is the difference between GPL, MIT, and Apache licenses?

The GPL license is a strict copyleft license that requires all changes and derivative works to also be under the GPL. MIT and Apache are permissive licenses that offer more freedoms, with Apache including additional patent protection. The choice between these licenses determines how you can use the software in your projects.

GPL (General Public License) protects the freedom of software through the copyleft principle. If you use and distribute GPL-licensed software, you must:

• provide or make available the source code
• also place your changes under the GPL
• clearly identify the license terms

The MIT license is the simplest permissive license. It allows virtually anything as long as you:

• retain the original copyright notice
• include the license terms in copies of the software

The Apache license is similar to the MIT license, but also offers:

• explicit patent protection for users
• protection against trademark infringement
• clearer rules for contributions to the software

Practical examples of use: Use the GPL for community projects that should remain open. The MIT license is suitable for libraries that are to be widely distributed. The Apache license is ideal for corporate projects where patent protection is important.

Which license should you choose for your project?

The right license choice depends on your business model, project goals, and desired community involvement. Choose the GPL for maximum openness, the MIT license for maximum distribution, and the Apache license for corporate projects with patent protection. Also consider the licenses of the software components you are already using.

For community-driven projects, the GPL is suitable because it ensures that all improvements benefit the community. This choice encourages contributions from other developers and prevents companies from using your work without compensation.

For libraries and tools, the MIT license is often the best choice. The low legal hurdle leads to higher adoption and more feedback. Many successful JavaScript libraries use the MIT license for this reason.

For enterprise software, the Apache license offers the best balance between openness and legal certainty. Patent protection prevents legal problems and makes the project more attractive to other companies.

Important decision factors:

• Do you want to allow commercial use without an obligation to return?
• Is patent protection relevant to your project?
• What licenses do your dependencies use?
• How important is maximum distribution compared to community control?

What happens if you misuse open source licenses?

License violations can lead to costly litigation, claims for damages, and the obligation to publish your own source code. Common mistakes include ignoring copyleft provisions, missing license notices, and using incompatible licenses in a project. Preventive measures such as license audits protect against legal problems. There are also specialized service providers and software offerings that take over the analysis of the code used.

Legal consequences of license violations are diverse:

• Cease and desist orders that can stop your software distribution
• Claims for damages for lost license fees
• Obligation to subsequently publish the source code
• Attorney and court costs

Common mistakes in practice arise from a lack of awareness:

• GPL software in proprietary products without source code publication
• Removal or modification of copyright notices
• Mixing incompatible licenses without considering the implications
• lack of documentation of used open source components

Companies can protect themselves by conducting regular license audits, training developers, and using tools for automatic license detection. A clear guideline for the use of open source software helps to avoid problems from the outset.

How credativ® helps with open source licensing issues

We support companies in the practical use of open source software through comprehensive consulting and practical implementation assistance. Our team of Linux specialists and open source experts knows many pitfalls and helps you avoid them while making the most of the benefits of free software.

With over 20 years of experience in the open source field, we understand both the technical and legal challenges. We help you to use open source software safely and effectively in your IT infrastructure without taking legal risks. Our comprehensive services cover all aspects of open source consulting.

Contact us for a non-binding consultation on your open source deployment. Together, we will develop a strategy that harnesses the innovative power of open source software for your company.

About the author

Peter Dreuw

Head of Sales & Marketing

about the person

Peter Dreuw arbeitet seit 2016 für die credativ GmbH und ist seit 2017 Teamleiter. Seit 2021 ist er Teil des Management-Teams als VP Services der Instaclustr. Mit der Übernahme durch die NetApp wurde seine neue Rolle "Senior Manager Open Source Professional Services". Im Rahmen der Ausgründung wurde er Mitglied der Geschäftsleitung als Prokurist. Sein Aufgabenfeld ist die Leitung des Vertriebs und des Marketings. Er ist Linux-Nutzer der ersten Stunden und betreibt Linux-Systeme seit Kernel 0.97. Trotz umfangreicher Erfahrung im operativen Bereich ist er leidenschaftlicher Softwareentwickler und kennt sich auch mit hardwarenahen Systemen gut aus.

View posts