Programmers Stack Exchange is a question and answer site for professional programmers interested in conceptual questions about software development. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm currently planning on implementing API for HgLab and the obvious role model for me here is GitHub.

My API obviously won't be an exact copy due to inherent differences between Mercurial and Git and due to different tasks GitHub and HgLab solve, but similarity will be quite clear.

How ethical of me will it be to copy their API to a significant extent? Is the API design copyrightable?

share|improve this question
Inspiration is commonplace. And an API that is designed to achieve almost the same effect and chooses the same style (for example a REST API) will look similar, even if it's not copied. That's all I'm saying. – Joachim Sauer Oct 17 '12 at 14:51
The question of whether an API can be copyrighted has shown up on the US news a few times lately. There are at least some US lawyers who are willing to argue that APIs can be copyrighted. Whether those lawyers are right is a more difficult question. – Brian Oct 17 '12 at 14:53
@Brian - Oracle found that the code can be copyrighted but the interface itself cannot be. – Ramhound Oct 17 '12 at 19:17
up vote 1 down vote accepted

I am not a lawyer. If you are genuinely worried about this you should consult one.

It is typically considered fine to duplicate an API as long as you don't look at the implementation at all. For instance, this is what the Wine project does with the Win32 API. In Oracle's recent court case against Google, one of Oracle's arguments was that Google was not allowed to copy Oracle's APIs for Java, however, the court did not agree with this argument.

share|improve this answer
Actually they did agree with Google, Google was only found guility of copying 9 lines of code, their blackbox copying was found to be legit. – Ramhound Oct 17 '12 at 19:18
@Ramhound that's what my answer says. The court disagreed with Oracle's argument that Google wasn't allowed to copy the API. – Dirk Holsopple Oct 17 '12 at 19:25

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.