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 (CC) is a global non-profit organisation which enables the sharing and reuse of copyrighted material by providing free ready-made machine-readable license agreements.  

The first version of the Creative Commons licenses was released in 2002. The current version, 4.0, was released in 2013. 

CC licenses may be applied to any type of work - research articles, conference papers, books, reports, educational resources, research data, images, and many other types of material in digital or printed form.  

Every CC license works around the world and lasts as long as the applicable copyright lasts.  

CC licenses are not an alternative to copyright - a work must be copyrighted in order to be licensed under a CC license. 

Under a CC license, the copyright ownership remains with the licensor. The licensor can only be the current copyright holder or rights holder, usually the author unless the author has transferred copyright to the publisher. Retaining copyright is one of the main principles of Plan S (the so-called ).

If third party material is being used in the work e.g. through permission of the copyright owner, the author of the new work can only license the part of the work to which they claim ownership. In this situation the author has to mark third party content to let others know that the entire new work may not be available under the selected CC license.  

It is not necessary to have just one license for the whole work, e.g. text and images can be shared under different CC licenses, but this has to be announced clearly.

CC licenses are non-exclusive.  for the same material at any time, often referred to as “double licensing” or “dual-licensing”, see Publishing and Commercialization

Note, that CC0 is a waiver, not a CC license. When CC0 is applied to a work or research data, the copyright owner renounces all rights, also the right to be named as an author. However, when CC0 material is used in research, the guidelines on good research practice should be followed, that is, the sources and authors should be named. Research data is often published with CC0 in order to avoid attribution stacking. With CC0 the attribution of authors is not a required license term, but authors can state how they wish to be named according to good scientific practice. 

CC licenses are based on four basic terms:

Attribution (BY): You must always provide credit to the original author. 

Share-Alike (SA): If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.

Non-Commercial (NC): You may not use the material for commercial purposes.

No-Derivatives (ND): You may not distribute modified versions of the work.

CC licenses

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Attribution CC BY 

The most permissive of the Creative Commons licenses which allows for maximum dissemination and use of the licensed work. The license permits others to use, reproduce, disseminate or display the article in any way, including for commercial purposes as long as they credit the author for the original creation. It can also be used in digital research such as data mining and long-term preservation independent of publishers. 

Major funders currently only accept the CC BY 4.0  license as compliant with their policy.  

Attribution-ShareAlike CC BY-SA  

The license lets others remix, tweak, and build upon the work, as long as they credit the copyright holder and license their new creations under the identical terms. CC BY-SA can be used  for teaching materials. 

Attribution-NoDerivatives CC BY-ND 

The license allows for redistribution, commercial and non-commercial, as long as the work is passed along unchanged and in whole, with credit to the copyright holder. 

Attribution-NonCommercial CC BY-NC  

This license lets others remix, tweak, and build upon a work non-commercially, and although their new works must also acknowledge the copyright holder and be non-commercial, they do not have to license their derivative works on the same terms. 

Attribution-NonCommercial-ShareAlike CC BY-NC-SA 

The license lets others remix, tweak, and build upon a work non-commercially, as long as they credit the copyright holder and license their new creations under the identical terms. 

Attribution-NonCommercial-NoDerivatives CC BY-NC-ND  

The most restrictive of the six main licenses, only allowing others to download works and share them with others as long as they credit the copyright holder, but they can’t change them in any way or use them commercially. 

! Note that CC licenses including the term NonCommercial (NC) are problematic concerning open access, because it is difficult to determine commercial usage, for example ResearchGate can be considered as commercial usage. Use of this license may also restrict research collaboration with companies.  

Most publishers will ask you to choose a Creative Commons (CC) license when publishing your work Open Access. The majority offer CC  BY 4.0  license for this purpose. Some journals may charge a higher open access publication charge for the use of CC BY 4.0 compared to the prices for publishing under the other CC licenses. 

Hybrid open access journals may offer a variety of different Creative Commons licenses, usually CC BY, CC BY-NC, or CC BY-NC-ND. 

Some publishers offer their own licenses over the content for which they get copyright. These licenses may provide permissions to read, download, use, re-post, remix, and perform other actions on the content, for commercial or non-commercial purposes. They are also often more restrictive than the Creative Commons licenses. 

Publishers may also specify the license that is applied to the work  when shared through green open access (uploading the accepted author's manuscript to an institutional repository). For example, Elsevier specifies that a CC BY-NC-ND license is required.