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Payless Health - Licensing FAQs

If you are interested in contributing guidance material or software to Payless Health, please read the following FAQs.

Please note that One Fact, the 501(c)(3) non-profit organization that builds Payless Health, does not provide legal advice, and this is not intended as a substitution for professional legal advice. If you have questions regarding open source and open content licensing generally or questions about specific licenses, please consult with your own legal counsel.

What license is One Fact’s code released under?

Code written by One Fact for Payless Health is made available under the Apache License, version 2.0 (Apache-2.0):

Like virtually all open source software, One Fact’s software relies upon a variety of other open source projects and dependencies, many of which may be under other open source licenses.

What licenses are One Fact’s documentation and articles released under?

Non-software content such as documentation and articles published by One Fact are, in most cases, published under the Creative Commons Attribution-ShareAlike 4.0 International License (CC-BY-SA-4.0):

As described in more detail below, in some cases where required by third party contributors, we may make available certain articles on our website under the Creative Commons Attribution-NoDerivatives 4.0 International License (CC-BY-ND-4.0):

How can I contribute code to Payless Health?

We are very grateful to the community of developers and experts that give their time and hard work for the benefit of everyone!

In order to help ensure that the code and content made available by One Fact can be redistributed under the licenses described above, we use a few basic contribution processes which are based on widely-used practices in the broader open source software community.

Contributions of code to One Fact should be licensed under Apache-2.0.

If you are contributing a new repository, please ensure that it contains a LICENSE file in the root directory with the full Apache-2.0 license text.

We also encourage the use of SPDX short-form license identifiers in source code files, to help communicate license information, e.g.:

SPDX-License-Identifier: Apache-2.0

Finally, please ensure that your Git commit messages for contributions include a Developer Certificate of Origin (DCO) sign-off statement with your name and email address, in the following form:

Signed-off-by: Full Name <>

This sign-off process is based on the process used by the Linux kernel and many other open source projects to receive contributions.

How can I contribute documentation and articles to Payless Health?

Contributions of documentation and articles to Payless Health (sponsored by One Fact) should be licensed under CC-BY-SA-4.0.

The license should be indicated in the documentation or article itself, wherever possible. We would generally recommend a format similar to the following:

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (CC-BY-SA-4.0), available at
SPDX-License-Identifier: CC-BY-SA-4.0

Additionally, as with contributions of code as described above, please include a DCO sign-off statement with your name and email address, in the following form:

Signed-off-by: Full Name <>

If you are contributing the documentation or article via a Git pull request, please include the DCO sign-off statement in the Git commit message. If you are contributing by email to One Fact, please include it in the email message.

Please note that articles being instead contributed under CC-BY-ND-4.0 should modify the text of the notice accordingly.

Does One Fact require a Contributor License Agreement (CLA) for contributions to Payless Health?

No. Instead of a CLA, One Fact receives contributions of code and other content using the Developer Certificate of Origin (DCO) sign-off process described above.

Does contributing code or content to Payless Health mean that I lose ownership of my contributions?

No. Contributors to Payless Health & One Fact retain ownership of their copyrights in their contributions. Code and other content is licensed to One Fact and the broader community under the licenses described above.

The Developer Certificate of Origin (DCO) sign-off process is understood by One Fact to indicate that contributors certify their ability to contribute their code and other content under the license indicated in the applicable file, but it does not transfer ownership of contributions or copyright to One Fact.

If I contribute an article, what if someone later changes it to misrepresent my statements or to add themselves as a reference source for my article?

There are (at least!) two mechanisms in place to help prevent this. First, as a matter of policy, when a third party contributes an article to One Fact, we will not change that article in a way that would alter the meaning or would promote a different author or organization in connection with it. We also will not accept edits from third parties that would do any of these things.

Additionally, although a Creative Commons license cannot be revoked, the Creative Commons licenses used by One Fact enable authors to have their attribution information removed upon request. As stated in Section 3(a)(3) of CC-BY-SA-4.0, “If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.” If you contributed content to us under CC-BY-SA-4.0 and you wish to exercise this right, please email us at with your request and we will act upon it promptly.

Why are some articles on the Payless Health website published under a “No Derivatives” license?

As an organization dedicated to furthering open science and open content, we make all of our own developments available to the public under open source software licenses (Apache-2.0) and licenses approved for free cultural works (CC-BY-SA-4.0). Additionally, wherever possible, we encourage contributors of materials to One Fact to make their contributions available to us and the public under the same licenses.

Because of the sensitive health-related nature of the space in which Payless Health & One Fact participate, some contributors of articles may only agree to allow One Fact to republish their content under a “No Derivatives” Creative Commons license. As described on the Creative Commons website, this means that “If you remix, transform, or build upon the material, you may not distribute the modified material.”

We strongly encourage our contributors to allow their articles and related content to be made available under the “ShareAlike” CC-BY-SA-4.0, in order to allow content to be remixed, built upon and released under the same license. And as described above, under CC-BY-SA-4.0 an author can require One Fact (or others) to remove the author’s attribution information for any or not reason, such as if they do not want their information associated with a remixed version.

However, where required by an author, in some cases One Fact may make the determination that the public interest is better served by making an article available under CC-BY-ND-4.0. Even if that does not enable redistribution of remixed versions, it will at least enable the public to gain from the learnings and information communicated in the article.

We are very grateful to all of our contributors for their willingness to make their content and knowledge publicly available! Please email us at with any questions.

Payless Health is sponsored by the Brown Institute at Columbia and Stanford ( and Patient Rights Advocate (