Stack Overflow says public contributions are licensed under Creative Commons Attribution ShareAlike, with the version depending on the post date. CC BY-SA requires credit and, for adaptations, the same license. Copying snippets into a product without tracking them creates a license gap. Not legal advice.
What the platform states
Stack Overflow's help page says all publicly accessible user contributions are licensed under Creative Commons Attribution-ShareAlike. Content before 2011-04-08 UTC is CC BY-SA 2.5. From 2011-04-08 up to but not including 2018-05-02 it is CC BY-SA 3.0. On or after 2018-05-02 it is CC BY-SA 4.0. The license for each revision is on the post timeline.
What CC BY-SA 4.0 asks for
The Creative Commons deed for version 4.0 lists two main terms. Attribution means you must give appropriate credit, provide a link to the license, and indicate if changes were made. ShareAlike means that if you remix, transform or build upon the material, you must distribute your contributions under the same license as the original. The deed also says it only highlights key features and is not the license itself.
Creative Commons FAQ also says CC does not recommend its licenses for computer software. That does not make the license disappear for a copied snippet. It means the fit with software workflows is awkward and worth a conversation with counsel.
Why this matters for a startup
A snippet pasted into a core module has no package metadata, so no scanner lists it. It sits outside your SBOM. An investor who asks "do you have copied third party code?" is asking about exactly this. Answer with a policy and a record.
A practical policy
| Option | When it fits |
|---|---|
| Do not paste, write your own | Core product code |
| Paste with attribution comment and log | Small, clearly bounded helper, approved by the owner |
| Replace with a library under an allowed license | Anything you would otherwise copy more than a few lines of |
Whichever option you choose, keep it consistent and written down.
Steps if you already have snippets
- Search the code for comments with Stack Overflow links, and for code you know came from forums or blogs.
- Record each one: file, source link, post date, license version.
- Decide per snippet: keep with attribution, rewrite from scratch, or replace.
- Add a contributing note telling developers how to handle new snippets.
- Consider a snippet detection tool, understanding it will not catch everything. See vendored code and scanning blind spots.
AI assistants make the question wider
Generated code can also resemble public code. The post on AI generated code questions in diligence covers how to answer that.
Safeguard's SBOM and dependency scanning cover packages, not pasted snippets, so a snippet register stays a process you run yourself.
Quick check
Does a code comment with the link satisfy attribution?
The deed asks for appropriate credit, a link to the license and an indication of changes. A comment can carry those, but confirm the details with counsel.
Is a three line snippet covered?
Whether a small piece is protected at all is a legal question. Do not assume the answer. Ask counsel and write down the decision.
Sources
- Stack Overflow, what is the license for the content I post
- Creative Commons, CC BY-SA 4.0 deed
- Creative Commons FAQ
Last reviewed: 19 October 2026.
