Creative Commons Licenses Explained: What's the Difference Between CC-BY, CC-BY-NC, CC-BY-ND? ​

Written: October 2026. License terms follow the official Creative Commons versions. This article is for informational purposes only and does not constitute legal advice.

Every model weight you download from Hugging Face, every dataset you grab from Kaggle, every image you find online — they're probably not licensed under MIT, Apache, or GPL. They use Creative Commons (CC) licenses.

These aren't software licenses. CC licenses are designed for creative content: text, images, audio, video, datasets, model weights, 3D print files, music. They answer different questions than software licenses: not "can you modify code, can you make it proprietary," but "can you use it commercially, must you attribute, can you adapt, can you add restrictions."

Series 13 mentions CC-BY, CC-BY-NC, CC-BY-NC-ND in several places but never explains them in detail. This article fills that gap.

1. The Four CC License Modules ​

CC isn't a set of independent licenses — it's a combination of four condition modules. Any CC license you see is built from these four:

The four modules arranged from most to least permissive:

• CC0: Waives all rights, enters public domain, no attribution required
• CC-BY: Most permissive CC license, only requires attribution
• CC-BY-SA: Attribution + ShareAlike (similar to GPL's viral nature)
• CC-BY-NC: Attribution + Non-commercial
• CC-BY-NC-SA: Attribution + Non-commercial + ShareAlike
• CC-BY-ND: Attribution + No derivatives
• CC-BY-NC-ND: Most restrictive, attribution + non-commercial + no derivatives

Note: There's no "CC-BY-NC-ND-SA" combination. ND and SA are mutually exclusive — you can't simultaneously require "no derivatives" and "derivatives must use the same license."

2. CC0: Does It Really Waive All Rights? ​

CC0 stands for "CC Zero," meaning the author waives all copyright and related rights, placing the work in the public domain. You can copy, modify, use commercially, redistribute — no attribution needed, no conditions.

Sounds free, but there are two catches:

1. CC0 doesn't waive patent or trademark rights. If the work contains patented technology or registered trademarks, CC0 only waives copyright, not other rights.

2. CC0 code may still be subject to other licenses. If a GitHub repo has CC0 code but depends on GPL libraries, you still must comply with GPL when using it. CC0 only covers the author's own contributions.

3. Some jurisdictions don't recognize "public domain." In civil law countries like Germany and France, authors' moral rights cannot be waived. CC0 there degrades to "the most permissive license possible," but legally doesn't equal true public domain.

Practical advice: When you see CC0, you can use it freely, but check dependencies and attached rights.

3. CC-BY: Attribution Only, Everything Else Allowed ​

CC-BY is the closest CC license to open source. You can freely use, copy, modify, use commercially, redistribute — the only obligation is to attribute in the way the author specifies.

How to Write Attribution ​

CC-BY requires you to retain:

• Author name (or pen name, nickname)
• Work title
• License name and link (official link to CC-BY 4.0)
• If you modified the work, note "modified"

Correct example:

"Stable Diffusion v1.5" by Stability AI, licensed under CC-BY 4.0. Modified by adding LoRA adapters.

Incorrect example:

Using it directly without mentioning the source.

CC-BY in Model Weights ​

Many model weights use CC-BY 4.0, such as:

• PocketTTS (CC-BY 4.0)
• Parakeet-TDT 0.6B v3 (CC-BY 4.0)
• Citrinet ASR (CC-BY 4.0)

These models allow commercial use, but you must attribute the source in your documentation, product page, or user manual. Missing attribution is a common compliance accident.

4. CC-BY-SA: Viral Sharing from Code to Content ​

CC-BY-SA adds ShareAlike to CC-BY: if you adapt, transform, or create based on the original work, you must release the adapted work under the same license.

This is very similar to GPL's viral nature:

• GPL: If you modify GPL code, the modified code must be released under GPL
• CC-BY-SA: If you adapt CC-BY-SA content, the adapted content must be released under CC-BY-SA

What Counts as "Adaptation"? ​

• Translation: Translating an English article to Chinese is adaptation
• Remixing: Mixing two music tracks together is adaptation
• Fine-tuning a model: Doing LoRA fine-tuning on CC-BY-SA weights is adaptation
• Quantizing a model: Converting CC-BY-SA weights from FP16 to INT8 is a technical conversion, not adaptation (CC 4.0 explicitly excludes "exact reproduction")

Boundaries of Viral Sharing ​

If you just collect multiple works together (like a model collection pack) without modifying individual works, this doesn't trigger SA obligations. But if you merge multiple works into a new work (like combining two datasets into one), the new work must be released under CC-BY-SA.

Practical advice: When you see CC-BY-SA, ask yourself "Will I adapt it?" If just using as-is, no problem; if modifying, the result must use the same license.

5. CC-BY-NC: Where Are the Boundaries of Non-Commercial Use? ​

CC-BY-NC adds NonCommercial to CC-BY: you cannot use the original work for profit-making purposes.

What Counts as "Commercial Use"? ​

CC's official definition is "primarily intended for or directed toward commercial advantage or private monetary compensation." Specifically:

Counts as commercial use:

• Using a CC-BY-NC model for voiceover work, taking commercial orders
• Using a CC-BY-NC dataset to train a model, selling to clients
• Using a CC-BY-NC tool internally at a company (the company is a for-profit organization)
• Publishing a video made with CC-BY-NC music on YouTube, with ad revenue enabled

Doesn't count as commercial use:

• Personal learning, research
• Classroom demonstrations at school (non-profit educational institution)
• Using in a non-profit organization's internal project
• Integrating in an open source project (the project itself doesn't charge)

Gray Areas ​

Some scenarios have blurry boundaries:

• Content creator monetization: You use a CC-BY-NC model to generate voiceovers, publish on your Bilibili account, and Bilibili has creator incentives. Does this count as commercial use? CC hasn't officially answered, but leans toward yes — because you receive economic benefit through the platform.
• Open source project commercialization: You train a model based on a CC-BY-NC dataset, put it on GitHub as open source, but accept sponsorships. Does this count as commercial use? Disputed — if sponsorships are voluntary and not mandatory, maybe not; if sponsorships are the project's main income source, maybe yes.
• Education and training: You're a training institution teacher, using a CC-BY-NC tool for teaching demonstrations. Does this count as commercial use? Yes — training institutions are for-profit organizations.

NC's Impact on Model Weights ​

Many model weights use CC-BY-NC, such as:

• Stable Audio Open (CC-BY-NC, non-commercial music generation)
• Some Hugging Face datasets (CC-BY-NC)

These models don't allow commercial use. If you want to use them for commercial products, you must contact the author for a commercial license, or switch to models with different licenses.

Practical advice: When you see CC-BY-NC, ask yourself "Will I use it to make money?" If yes, can't use it; if no, can use it.

6. CC-BY-ND: No Derivatives, Only Use As-Is ​

CC-BY-ND adds NoDerivatives to CC-BY: you cannot modify, adapt, or transform the original work.

What Counts as "Derivative"? ​

• Translation: Yes
• Remixing: Yes
• Cropping an image: Yes
• Fine-tuning a model: Yes
• Quantizing a model: No (CC 4.0 explicitly excludes technical conversions)
• Format conversion (like PNG to WebP): No

Use Cases for ND ​

CC-BY-ND is typically used when authors want to maintain work integrity:

• Official documentation (don't allow others to randomly modify)
• Artistic works (don't allow others to create derivative works)
• Standard datasets (don't allow others to modify and redistribute under the original name)

Practical advice: When you see CC-BY-ND, ask yourself "Will I modify it?" If yes, can't use it; if no, can use it as-is.

7. CC-BY-NC-ND: Most Restrictive ​

CC-BY-NC-ND combines NC and ND restrictions: you can neither use commercially nor adapt.

This is the most restrictive CC license. You can only use and share as-is, can't make money, can't modify.

Typical use cases:

• Authors want works widely distributed but don't want others making money or randomly modifying
• Official standard documents, specifications
• Artists' original works

Practical advice: When you see CC-BY-NC-ND, unless you're just using it for personal learning, don't touch it.

8. CC License Version Differences ​

CC licenses have multiple versions: 2.0, 2.5, 3.0, 4.0. 4.0 is the current latest version and the recommended one.

Main Improvements in 4.0 vs 3.0 ​

• Internationalization: 4.0 no longer relies on specific country legal terms, applicable globally
• Attribution obligations simplified: 3.0 required retaining all authors' attribution, 4.0 only requires retaining "reasonable attribution"
• SA compatibility enhanced: 4.0 explicitly allows compatibility with GPL, Apache, and other software licenses
• Database rights: 4.0 explicitly covers database rights (sui generis database rights)

Practical advice: If a work has multiple CC versions available, prefer 4.0. If a work already specifies a particular version (like CC-BY 3.0), you can only use it under that version.

9. Relationship Between CC and Software Licenses ​

CC licenses aren't designed for software code, but many people use them to license model weights, datasets, documentation. This raises a question: can CC and software licenses (MIT, Apache, GPL) coexist?

Answer: Yes, but be careful.

• CC-BY, CC-BY-SA, CC0 are compatible with software licenses. You can use CC-BY documentation and MIT code in the same project.
• CC-BY-NC is incompatible with GPL. GPL requires "no additional restrictions," but CC-BY-NC adds a "non-commercial" restriction.
• CC-BY-ND is incompatible with GPL. GPL requires "allow modifications," but CC-BY-ND prohibits modifications.
• CC-BY-NC-SA is incompatible with GPL. GPL requires "allow commercial use," but CC-BY-NC-SA prohibits commercial use.

Practical advice: If a project uses both CC and software licenses, check if they're compatible. If not, you need to license them separately (e.g., code under MIT, documentation under CC-BY).

10. Common CC Licenses in Model Weights ​

From the 94 local AI apps we've cataloged, these use CC licenses:

Note: Model weights using CC licenses doesn't mean training data also uses CC licenses. The weight's license governs "can you use this model," while training data licenses govern "how was this model trained." These are two separate issues.

11. Quick Decision Table ​

For any CC license, use this table to quickly judge:

Notes: ✅ means allowed, ❌ means prohibited, — means not applicable.

12. How to Properly Attribute ​

If you use any of CC-BY, CC-BY-SA, CC-BY-NC, CC-BY-ND, CC-BY-NC-SA, CC-BY-NC-ND, you need to attribute.

What Should Attribution Include? ​

CC 4.0 requires you to retain:

• Author name (or pen name, nickname, organization name)
• Work title (if the author specified one)
• License name and link (e.g., "CC-BY 4.0" + https://creativecommons.org/licenses/by/4.0/)
• Copyright notice (if the author specified one)
• Modification notice (if you modified the work)

Where Should Attribution Go? ​

• Documentation: In an "Attribution" section at the beginning or end
• Code: In README or LICENSE file
• Video: In video description or end credits
• Audio: In audio description or intro/outro
• Model weights: In model card or README

Attribution Format ​

CC's recommended format:

"[Work title]" by [Author name] is licensed under [License name].

For example:

"Stable Diffusion v1.5" by Stability AI is licensed under CC-BY 4.0.

13. Common Misconceptions ​

Misconception 1: CC-BY-NC means "can't make money" ​

Not exactly. CC-BY-NC prohibits "use primarily intended for commercial advantage," not "can't make money." If you use a CC-BY-NC model to make an open source project that doesn't charge but accepts sponsorships, this might not count as commercial use (disputed). But if you use a CC-BY-NC model to make a SaaS service that users pay for, this definitely counts as commercial use.

Misconception 2: CC-BY-SA is the same as GPL ​

Not exactly. CC-BY-SA's viral nature is similar to GPL, but CC-BY-SA governs content, GPL governs code. You can't mix GPL code with CC-BY-SA documentation and say "they're both viral licenses."

Misconception 3: CC0 means "no copyright" ​

Not exactly. CC0 is the author waiving copyright, but copyright still exists (the author just doesn't enforce it). In some jurisdictions, authors' moral rights cannot be waived, so CC0 there doesn't equal true "no copyright."

Misconception 4: CC licenses only apply to artistic creations ​

Wrong. CC licenses apply to any content: text, images, audio, video, datasets, model weights, 3D print files, maps, databases. Many AI model weights use CC licenses.

Misconception 5: CC-BY-ND doesn't allow any modifications ​

Not exactly. CC-BY-ND prohibits "derivatives" (adaptation, transformation, creating new works based on the original), but allows technical modifications (format conversion, compression, quantization). For example, you can convert a CC-BY-ND image from PNG to WebP — this doesn't violate ND.

14. Relationship to Other Articles ​

• Series 13 #2 (Open Source Software Licenses Explained): Covers software licenses like MIT, Apache, GPL. This article covers CC licenses. The two complement each other.
• Series 13 #8 (Derivative Model License Chains): Covers whether quantized, LoRA, fine-tuned models are subject to original licenses. This article's CC-BY-SA and CC-BY-ND sections are relevant.
• Series 13 #10 (Non-Commercial Publishers): Covers why universities, labs, and individual developers use CC-BY-NC. This article's CC-BY-NC section is relevant.
• skill/licensing/local-ai-audiocpp-model-licenses: Covers licenses for models in audio.cpp. Several models use CC-BY 4.0.

15. References ​

• Creative Commons Official Website
• CC License 4.0 Full Text
• CC License Comparison Chart
• CC Attribution Best Practices
• Hugging Face Model License Guide

Disclaimer: This article is for informational purposes only and does not constitute legal advice. For specific compliance questions, consult a professional lawyer. License terms follow each project's official LICENSE file; translations are not authoritative.