Good Faith and Fair Dealing in Open Source – Why it’s Important for You

The culture of open source software is all about sharing and contributing for the mutual benefit of the community. It’s no surprise that the legal concept of “good faith and fair dealing” is an important part of open source software licensing. Good faith means “honest intent to act without taking an unfair advantage over another person or to fulfill a promise to act, even when some legal technicality is not fulfilled.”[1]

Open source wasn’t invented by lawyers – it was invented by and for software developers that want their code to be used. It’s important that developers who use open source act fairly and honestly for both ethical and legal reasons. When legal action is taken against a company for misusing open source code, the goal of the action is usually to right the wrong, rather than to make a profit. Legal experts tell us that the most important thing for the defense is the ability to demonstrate good faith.

How do you use OSS fairly, and how do you prove that you acted in good faith? First, you must be able to show that you tried to use the software correctly and intended to honor the terms of the license. That boils down to two things:

  • Having an orderly process in place for evaluating and adopting open source libraries and code in your projects
  • Documenting that process including history, changes and approvals – not just a snapshot of the current state

You should also use code scanners periodically to identify rogue open source code in your project. But make sure to instill the right adoption processes in your team because scanners can, at best, show the current state of your code. They do not record when, how and why the open source code got there in the first place. They also do not tell you anything about the open source libraries that you are linked to, and any license dependencies that they include.

In short, to be fair to open source developers, and to show good faith, you need to implement and document an open source adoption process. As soon as you start, you’ll be on the road to demonstrating good faith, and reducing the risk of using open source in your commercial products.

[1] Legal dictionary at