I am considering the usage of various open source libraries in a closed source Android app. The libraries are released under various licenses (MIT, BSD modern, Apache 2.0) which allow this kind of usage, but require that the copyright notice is made available verbatim with the application.
I have seen various approaches, at least four:
- A submenu triggers a dialog where project names and relative licenses are displayed, e.g. Google apps.
- A message like “This app uses various projects released under license XXXX” is displayed on the app website. No notice is present inside the application or in the Play Store description, e.g. Whatsapp.
- No mention is done of the libraries being distributed with the application.
- Like 3, but the APK contains a
/licensefolder.
What is the best practice? Maybe something else? Are approaches #2 and #3 even in compliance?
As a passionate contributor to various open source projects, I would really go with #1. Unfortunately, I am not in charge, so I must be able to argue about #2 and #3 too and/or propose a better solution.
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Most OSS licenses don’t try to precisely prescribe what is expected, as they cannot reasonably know what environment they run in. After all, the freedom to run FOSS code in many environments is a fundamental part of what it means to be FOSS code.
Instead, there’s usually a clause that relies on implicit or contextual norms. For instance, the requirement can be to display all the copyright information in one place. Hiding some of the relevant copyright information in another location, just because you don’t own those copyrights can be seen as disingenuous. if you think your copyright belongs in dialog X, then you better place all copyrights there. If you find it acceptable to have only a link to a mobile webpage in your app, even for your own copyrights, it’s likely the FOSS copyright owners will accept this.
Note that “contextual norm” can be set by third parties. If Apple decides to have a form where you need to state copyrights, then that becomes the norm for all iPhone apps, and you must list FOSS copyrights along with your own.
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- A message like “This app uses various projects released under license XXXX” is displayed on the app website. No notice is present inside the application…
It’s moot whether BSD licenses allow that, but I could not imagine how the following clause from both MIT licenses (Expat and X11) could be read to make that possible:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
The exact terms vary from license to license, but most licenses require that the copyright message is somewhere where the end-user can find them. You can not assume that a regular end-user visits your website. And it is even less reasonable to assume that a regular end-user will unpack the APK file to look for the license files. Android end devices usually do not even provide the tools for doing this.
That means having a menu entry where the user can read the open source licenses is the most reasonable option of those you provided. An about-section which also includes your own copyright notice is a good place for this.
Just because others take license terms lightly is no excuse that you should do the same. Not complying to the license terms opens you up to a lawsuit from the creators of the library. There are non-profit open source organizations which sometimes finance such lawsuits when the case is high-profile enough. Talk to your legal department for further information. You don’t have a legal department? Get a lawyer. In todays world you can’t do business without legal advise.
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