What do BY, SA, NC and ND mean?
Those four letters under a photograph, BY-NC-ND 4.0, are a Creative Commons license. They tell you exactly what you may do with the image. What do BY, SA, NC and ND mean? Each is a condition. Together they form one of the six standard licenses.
BY means you must credit the creator. SA means any adapted version you share must carry the same license. NC means the use cannot be for commercial advantage or monetary compensation. ND means you may share the work unchanged but you cannot share an adaptation.
None of these conditions apply if your use is already authorised by a copyright exception such as fair use or fair dealing. Those operate separately from the license. Open the exact source page, record the license version and creator, and check whether your planned activity, share unchanged, adapt, or use commercially, is blocked by the conditions you see.
What Each Condition Requires
BY, Attribution
You must keep the attribution information the licensor supplied: the creator's name, a copyright notice, a reference to the license, a warranty disclaimer if present, and a link to the material. You must also link to the exact license and indicate any modifications. In version 4.0 this can be done in any reasonable manner for the medium. A credits page at the end of a video is fine if each work is clearly mapped to its credit. You cannot imply endorsement.
Example: A photographer releases a cityscape under CC BY 4.0. You use it in a blog post. Add a caption crediting the photographer and linking to the license. You do not need to ask permission.
SA, ShareAlike
ShareAlike only matters when you create and share Adapted Material. If you put the work unchanged into a collection alongside other separate works, SA does nothing. But if you edit, translate or remix the work and then share the result, your adaptation must carry the same license, CC BY-SA 4.0, or one the official compatibility list names as compatible. Do not assume two SA licenses are compatible. They are not unless Creative Commons says so.
Example: A musician releases a song under CC BY-SA 4.0. You remix it. When you publish your remix, you must license it under CC BY-SA 4.0 as well. You cannot choose a different license.
NC, NonCommercial
Version 4.0 defines NonCommercial as not primarily intended for or directed toward commercial advantage or monetary compensation. The identity of the user, a business, a charity, an individual, does not decide it. Advertising, sponsorship and fundraising all require context. There is no bright line. If your use has material commercial risk, get separate permission or local legal advice.
Example: A graphic designer releases icons under CC BY-NC 4.0. You work for a museum. You can use the icons in a free exhibition guide. You cannot sell posters of those icons. If you are unsure whether your use is commercial, treat it as risky and seek advice.
ND, NoDerivatives
You may share the work unchanged, even for commercial purposes if no other condition forbids it. You may not share an adaptation. What counts as an adaptation depends on copyright law. A few things are clear in version 4.0: translation is normally an adaptation. Synchronising music with a moving image is expressly Adapted Material. Changing format alone, converting a PDF to a plain text file, does not create an adaptation. Cropping, excerpting or combining may or may not create one; there is no universal rule.
Example: A writer releases a short story under CC BY-ND 4.0. Repost the entire story on your site with attribution. You cannot translate it into Spanish and share the translation.
The Six Licences And Two Public-Domain Tools
Creative Commons is a nonprofit organisation that publishes standard copyright licenses and public-domain tools. It is not a party to any individual license, does not register works, does not verify ownership, and does not give legal advice. The current suite has six 4.0 International licenses. All six require attribution. The six use different combinations of those conditions.
CC BY 4.0 allows sharing and adaptations, including commercial use, as long as you credit the creator. CC BY-SA 4.0 adds the condition that any shared adaptation must use BY-SA 4.0 or a compatible license. CC BY-ND 4.0 allows sharing including commercial sharing but forbids sharing adaptations. CC BY-NC 4.0 allows sharing and adaptations only for noncommercial purposes. CC BY-NC-SA 4.0 adds ShareAlike to the noncommercial restriction. CC BY-NC-ND 4.0 allows only noncommercial sharing of unadapted material.
Two tools are not licenses. CC0 is a public-domain dedication with a waiver, a fallback license where the waiver is not effective, and a non-assertion promise limited to remaining Copyright and Related Rights. It removes copyright and related-rights conditions as far as the affirmer is legally able. The Public Domain Mark changes no rights; it marks material believed free of known copyright restrictions worldwide. Neither guarantees that privacy, publicity, trademark, patent or other law permits a use.
Choosing A Licence
Only the copyright holder, or someone with express authority, may apply a CC license. Confirm joint authors, employment ownership and third-party inclusions first. Use version 4.0 for a new license unless you have a specific reason for an older one. No registration with Creative Commons is required. The official chooser helps create a notice but does not validate ownership.
Do not use a CC license for software code. Use a recognised free/open-source software license. Documentation and other non-code assets may carry separate CC licenses if they are clearly marked.
| Condition | What It Allows | What It Blocks |
|---|---|---|
| BY | Sharing and adaptations with credit | Use without attribution |
| SA | Sharing adaptations under the same licence | Sharing adaptations under a different licence |
| NC | Sharing and adaptations for noncommercial use | Use for commercial advantage or monetary compensation |
| ND | Sharing unadapted material | Sharing adaptations |
What Happens When You Get It Wrong
If you breach a condition under version 4.0, the license terminates automatically. It is reinstated automatically if you cure the violation within 30 days after you discover it. The licensor may also reinstate it expressly. Cure does not erase possible liability for the period of violation. Older versions have different termination language and no automatic 30-day mechanism.
The licensor can stop distributing the work or offer it under other terms, but cannot withdraw the license from people who already received it while complying. Dual licensing is permitted. Separate permission can waive a condition for a particular user.
Reuse Workflow
Open the original source page. Do not rely on a repost or a thumbnail. Record the creator, source URL, exact license and version, displayed notices, exclusions and the date checked. Confirm your intended activity against NC, ND and SA. Check non-copyright permissions: people depicted or recorded, brands, data, location restrictions, confidentiality and platform rules. Attribute in a reasonable manner, link the exact license, mark changes and avoid implying endorsement.
TASL, title, author, source, license, is a useful memory aid, not the complete legal text for version 4.0. You must also add an indication of changes and preserve supplied notices.
Collections And Adaptations
A collection keeps separate works separate. Each work keeps its own license. Adapted Material is based on and modifies the licensed work in a way that requires copyright permission. Only the adapter's contribution is covered by the adapter's license; notices for the original must remain. Combining material is not automatically lawful because each input uses a CC license. ND may block sharing the combination if it is an adaptation. SA may require a specific adapter's license. Two inputs can impose incompatible terms. Use the official compatibility chart and distinguish mere aggregation from an integrated adaptation.
Common Questions
Can I use a CC-licensed work without attribution if attribution is impossible?
No. The BY condition requires attribution. If it is impossible, the use is not permitted under the license. You must either find a way to attribute or not use the work.
If I use a CC BY-ND work on my website, can I change the file format?
Yes. Changing format alone does not create Adapted Material under version 4.0. You can convert a PDF to a plain text file and share it. But you cannot translate, edit or remix it.
Does the NC condition mean I cannot use a work if I am a business?
No. The identity of the user does not decide it. The question is whether the use is primarily intended for or directed toward commercial advantage or monetary compensation.
What happens if I share an adaptation under the wrong license?
The license terminates automatically in version 4.0. You must cure the violation within 30 days of discovering it. Liability for the period of violation may still apply.
Can I upgrade an older CC license on someone else's work to version 4.0?
No. A license already attached to someone else's work cannot be unilaterally upgraded by a reuser. Only the licensor can choose a new version.
Is CC0 the same as a CC BY license?
No. CC0 is a public-domain dedication, not a license. It aims to remove copyright conditions as far as the affirmer is legally able. CC BY retains copyright while granting permission with attribution.
If I credit the creator using TASL, have I met the attribution requirement?
Not for version 4.0. TASL is a useful mnemonic but the 4.0 legal code also requires you to indicate modifications and preserve any notices the licensor supplied. The deed lists all required elements.