Learn about the top open source licenses used by developers, including the 20 most popular open source licenses, and their legal risk categories.

If you’re a software developer, you probably use open source components and libraries to build software. You know those components are governed by different open source licenses, but do you know all the license details? In particular, the technical and somewhat convoluted licensing conditions that could pose compliance challenges?

The main problem in this context is that open source licenses are subjective. Their interpretation depends on the technical usage of the licensed software. Therefore, it’s difficult to determine the legal risks of using open source software, especially for developers, who are not usually legal experts. What developers need is a broad classification of licenses based on the risks they pose in terms of legal compliance.

Here, we’ve categorized the most popular open source licenses into three broad groups depending on their terms and conditions and their potential legal risks.

Top open source licenses by risk

Following is a list of the most popular open source licenses used by developers and their risk classification as described above. This classification is only a guideline and should not be used to make decisions about using open source software governed by each license. Developers should consult their legal/technical teams for further guidance regarding license compliance.