When source code, documentation and other content is contributed to a CNCF project, the copyrights in those contributions remain owned by the original copyright holders.
The copyrights are not assigned to CNCF. Instead, they are licensed for distribution as part of the project. Whether a project uses the DCO or a CLA, the original copyright holders retain their copyrights.
CNCF does not require or recommend that every contributor include their copyright notice in contributed files. See below for more details on why not.
Instead, CNCF recommends using a more general statement in a form similar to the following (where XYZ is the project's name):
- Copyright The XYZ Authors.
- Copyright The XYZ Contributors.
- Copyright Contributors to the XYZ project.
These statements are intended to communicate the following:
- the work is copyrighted;
- the contributors of the code licensed it, but retain ownership of their copyrights; and
- it was licensed for distribution as part of the named project.
By using a common format, the project avoids having to deal with names of copyright holders, years or ranges of years, and variations on the (c) symbol. This aims to minimize the burden on developers and maintainers as well as redistributors of the code.
Please note that it is not wrong, and it is acceptable, if a contributor wishes to keep their own copyright notices on their contributions. The above is a recommended format for ease of use, but is not mandated by CNCF.
If you are contributing on behalf of your employer, you may wish to discuss with your legal department about whether they will require you to include a copyright notice identifying them as the copyright holder in contributions.
If a file only contains code that originates from a third party source who didn't contribute it themselves, then you would not want to add the notices above. (In a similar vein, you wouldn't add a notice identifying you as the copyright holder either, if you didn't own it.) Just preserve the existing copyright and license notices as they are.
If, however, you add copyrightable content to a pre-existing file from another project, then at that point you could add a copyright notice similar to the one above.
You should not change or remove someone else's copyright notice unless they have expressly permitted you to do so. This includes third parties' notices in pre-existing code.
For additional details regarding attribution notices for third party code used in CNCF projects, see the CNCF attribution recommendations document.
There are several reasons why CNCF doesn't require or recommend trying to list every copyright holder for contributions to every file:
- Copyright notices are not mandatory in order for the contributor to retain ownership of their copyright.
- Copyright notices are rarely kept up to date as a file evolves, resulting in inaccurate statements.
- Trying to keep notices up to date, or to correct notices that have become inaccurate, increases the burden on developers without tangible benefit.
- Developers and maintainers often do not want to have to worry about e.g. whether a minor contribution (such as a typo fix) means that a new copyright notice should be added.
- Adding many different copyright notices may increase the burden on downstream distributors, if their license compliance processes involve reproducing notices.
- The specific individual or legal entity that owns the copyright might not be known to the contributor; it could be you, your employer, or some other entity.