Open Access

Open Licensing

What are open licences? How do they work?


What are open licences?

When content creators are happy for their work to be reused by other people, sharing that work under an open licence makes it easier for other people to understand exactly what they are allowed to do with the original material. Unlike traditional licences, which generally restrict rights to the copyright owner and/or content provider, open licences are all about enabling other people to reuse the content.

Not all open licences are the same. They differ in terms of the conditions attached to them, which may restrict - to a greater or lesser extent - how material can be reused. For example, most open licences require a user to give appropriate attribution, i.e. to say where they found the original and who made it. Other restrictions can include things like whether the user is able to modify the content or whether they can use it commercially.

This guide describes some of the most commonly-used open licences. The first half looks at Creative Commons licences and the second half looks at a few other kinds of open licence.


Creative Commons licences

Creative Commons (CC) is a network that aims to encourage international openness, sharing and collaboration around creative works. To help achieve this, CC has developed a set of modular licences that can be identified by acronyms and simple graphics, with the full terms and conditions of the licence detailed on the CC website.

Elements of CC licences

The foundation of all CC licences is the "CC0" licence, which is means the content is public domain - i.e. there are no restrictions on reuse. There are then various elements that can be added to define the specific kind of open licence that you need:

By Attribution (BY)

Any licence featuring the BY element requires users to acknowledge the original creator. Acknowledgement might be given in the form of a caption, reference, or in some other way that makes sense for the format in which the content is reused.

Non-Commercial (NC)

Any licence featuring the NC element informs users that they are not permitted to reuse the content for commercial gain. For example, you could not use any NC-licensed content if you were making an advert to help sell a product. However, this element just means that the creator does not want to grant unlimited permission for commercial reuse of their work - it may still be possible to request permission from them directly, on an individual basis.

No Derivatives (ND)

Any licence featuring the ND element informs users that they are not permitted to share adaptations of the content, only the original. For example, you could not resize or crop an ND-licensed image and then share the modified version with other people. However, this element just means that the creator does not want to grant unlimited permission for modifications to be made of their work - it may still be possible to request permission from them directly, on an individual basis.

Share-Alike (SA)

Any licence featuring the SA element requires users to apply the exact same licence whenever they share a modified version of the content. For example, if you adapted an SA-licensed image for use in your own powerpoint presentation, you would need to make the new version of the image available for others to use under the same licence.

Examples of CC licences

The above elements can be combined in different ways to produce the various licences. Additionally, licences will often have a version number at the end, indicating which revision of the licence has been used. The list below provides details of some of the available CC licences.

CC0 1.0

The CC0 licence indicates that the creator has waived their rights to the content worldwide, to the extent permitted by their local copyright law. The content can be copied, modified and shared for any purpose without needing to ask for permission or provide acknowledgement of the original creator. Version 1.0 of this licence is universal.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY 4.0

The CC BY licence indicates that the content can be copied, modified and shared for any purpose without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also indicate if changes were made and provide a link to the licence. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY-SA 4.0

The CC BY-SA licence indicates that the content can be copied, modified and shared for any purpose without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also indicate if changes were made and provide a link to the licence. Additionally, when the content is modified and shared elsewhere, it must appear under the same licence. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY-NC 4.0

The CC BY-NC licence indicates that the content can be copied, modified and shared without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also indicate if changes were made and provide a link to the licence. Additionally, the content cannot be used for commercial purposes without permission from the creator. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY-ND 4.0

The CC BY-ND licence indicates that the content can be copied and shared for any purpose without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also provide a link to the licence. Additionally, modified versions of the content cannot be shared without permission from the creator. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY-NC-ND 4.0

The CC BY-NC-ND licence indicates that the content can be copied and shared without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also provide a link to the licence. Additionally, the content cannot be used for commercial purposes without permission from the creator. Finally, modified versions of the content cannot be shared without permission from the creator. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.

CC BY-NC-SA 4.0

The CC BY-NC-SA licence indicates that the content can be copied, modified and shared without needing to ask for permission, as long as appropriate credit is given to acknowledge the creator of the original. Users of the content must also indicate if changes were made and provide a link to the licence. Additionally, the content cannot be used for commercial purposes without permission from the creator. Finally, when the content is modified and shared elsewhere, it must appear under the same licence. Version 4.0 of this licence is international.

The human-readable summary and the full legal text of this licence is available on the CC website.


Other open licences

As well as the Creative Commons licences described above, there are some other forms of open licence. These all permit certain types of reuse for openly-available content and are often developed with specific types of content or audiences in mind. Additionally, some content-providers may use their own form of open licence, detailing the conditions under which reuse is permitted on their own website.

Example: UK Open Government Licence (OGL)

The OGL was developed specifically for Crown Copyright works (i.e. content that is copyright of national governments and states that are part of the Commonwealth) in the UK. It is used by the UK government and a number of other public sector bodies in the UK. The licence is very similar to the Creative Commons BY licence, but includes some additional clauses. The full text of the licence is available on the National Archives website.

Example: Unsplash

Unsplash is an image-sharing website where all content is shared under a licence that is specific to Unsplash. The licence allows users to "download, copy, modify, distribute, perform, and use photos from Unsplash for free, including for commercial purposes, without permission from or attributing the photographer or Unsplash [...so long as the user does not...] compile photos from Unsplash to replicate a similar or competing service."