Creative Commons Licensing UI and Data Updates

Question

When we last updated you to clarify concerns and answer questions about our transition to version 4.0 of the CC BY-SA license we committed to posting updates to the UI and addressing unanswered questions. I am happy to announce that we have met these goals. As of now, UI and Data changes are live network-wide that include showing the relevant CC versions for all post revisions and comments on all sites, updating footers, API updates, and other related sites.

Before detailing the changes, I will first address some of the open questions that remain from our last update.

The previous update defined the license changing from CC BY-SA 3.0 to 4.0 on May 2, 2018. What happened on this date?

Prior to this date, the Terms of Service linked to CC BY-SA 3.0. On this date, the link changed to point to the 4.0 license. It was updated as part of a process that was not led by the Community Team and there was no public announcement at time due to an internal disconnect at the time of the release.

In that case, what about the change from CC BY-SA 2.5 to 3.0 that took place in April 2011? Shouldn’t that also affect a similar change?

We can now affirm that the same change in license that was posted on MSE to be effective as of April 8, 2011 (from version 2.5 to version 3.0) also could not have retroactively changed the license of content. The UI update laid out below will reflect this and will attribute each piece of content to the relevant license version.

Based on this, we will be adopting the following rules relating towards classifying the licenses attached to content published on the site:

• Content contributed before 2011-04-08 (UTC) is distributed under the terms of CC BY-SA 2.5.
• Content contributed from 2011-04-08 up to but not including 2018-05-02 (UTC) is distributed under the terms of CC BY-SA 3.0.
• Content contributed on or after 2018-05-02 (UTC) is distributed under the terms of CC BY-SA 4.0.

How do edits work? Can edits change the license on content that was already posted on the site?

• Every time that a piece of content is published, the work is published under the CC BY-SA version as defined above, based on the publish date.
• Every time a piece of content on the site is edited by a user, the editor creates a new version of the previous version. The new version of that work is considered to be republished and therefore governed under the CC BY-SA version in effect as of the day on which the edit was made.
• Each revision to a work creates a new version and is licensed separately. Thus current version of any piece of content (that appears on the site) is the most recent revision, and will have a license version based on the date on which that revision was published.
• This applies regardless of the size, the magnitude, or the significance of the edit that was made (except for the cases outlined below which are exceptions to this rule).
• New edits do not modify the license that is attached to an old revision of the same content. That old revision continues to be licensed under its original CC BY-SA version.

The UI changes as defined below will make it clear (through the timeline page) the license version that applies to every revision for each question, answer, and comment on all sites.

Are there any types of post edits that do not cause new licensed revisions or changes to the license on the post?

Yes, there are a few:

• Title or Body Rollbacks: do not create new licensed versions, as they do not add any content to that which was already published. The license on the post changes to the license on the rollback target revision.
• Tag applications to questions are considered to be meta-data and are not included in the content that is being licensed. Thus, tag-only edits or rollbacks do not effect any license changes or create new licensed versions
• The following system-initiated post edits do not create new licensed versions:
  • Commonmark migration edits
  • URL Rewrites
  • http to https replacements
  • MSO link to MSE link replacements
  • Insert/remove duplicate link edits

What license is applied to posts that are labeled Community Wiki?

When attached to a post, the Community Wiki label changes the display of the post on the site, and changes the way in which reputation is assigned.

Revisions to CW posts are to be treated in the same way as any other content revisions on the site with respect to the applicable license: licensed using CC BY-SA based on the date that the revision is made (which will be identifiable through the post timeline).

How can users upgrade the license of content that they own on the site from 2.5 or 3.0 to 4.0?

We are thinking about how we might enable users to mass update and republish their questions and answers (across all sites on the network) to change the license version from 2.5 or 3.0 to 4.0. This will require more discovery work on our end so we don't yet have a time frame on if or when this might be available, or how it would work. This feature would not add the ability to republish a subset of content. It would be all or none.

What will be the process for future license updates? Can I agree in advance to any license upgrades that Stack Overflow might adopt in the future for new content?

We will try our best to announce future license updates on the network at least one month prior to their being adopted for new content. This will give time for the Community to react and give feedback on the change.

Any future license version updates will only affect new content (or new revisions published based on existing content) that is published after the new versions are adopted on the network. There will be no way for a user to agree in advance to automatically adopt future license changes to their existing content.

So what changes have been made?

1. The timeline for every question and answer has been updated.
   1. The top of the timeline page (underneath the title of the post) lists the CC BY-SA version of the latest revision made to the post.
   2. A new column labeled “license” has been added to the timeline table.
   3. Each line in the timeline labeled as “history” where the action is “asked”, “answered”, or “edited” has the CC BY-SA version that is applied to the given revision.
2. The share post popover now includes a link to the license version applied to the post (decorated with an rel="license" attribute)
3. Comment versions:
   1. The tooltip on the comment date includes the license version applied to that comment on creation.
   2. If a comment had multiple revisions, the revision display that is available to moderators gives the license version that applied to each revision of the comment.
4. Footer text, other references:
   1. All references to the license throughout the site (including on the TOS) have been changed to “CC BY-SA” (or the same in lower-case).
   2. Text requiring attribution is no longer written. This is implicit from the definition of the “BY” section of the license name.
   3. The network footer has been updated to no longer reference version 4.0 of the license, and will now link to the /help/licensing page.
   4. Other references to the license in other sections of the sites on the network have been updated in the same way.
   5. Area 51 footer has been updated accordingly.
   6. The create chat page has been updated accordingly.
   7. The Public Terms of Service has been updated to use the correct format of "CC BY-SA" (instead of incorrect representations like "CC-BY-SA"). Current license version number (4.0) is included in text of the ToS (and not just in the link). A sentence has been added to the licensing section making reference to this post to give more details on how licenses are applied to content.
5. API models include a new field called content_license that will return the license associated with that record:
   1. Post
   2. Question
   3. Answer
   4. Revision
   5. Comment
   6. Question_Timeline (type=revision)
6. Data Exports & SEDE
   1. SEDE footer has been updated.
   2. SEDE query details updated to show the license applicable to that query.
   3. The following tables available on data.stackexchange.com will include (in the next refresh) a ContentLicense field: Posts, PostHistory and Comments.

We’re happy to hear any feedback you might have and will try to answer any questions as best as we can. However, please understand that we’re unable to provide any answers to questions about licensing that could possibly be interpreted as us giving legal advice.

Answer 1

Tag only edits trigger a license change.

status-completed

Update: Tag-only edits no longer trigger license changes

Please ignore the rollback.

Is this a bug? Are tags part of the post content?

If tags edits force a license change then any mass tag editing will update the licenses of every post affected.

Answer 2

bug status-completed

Update: tag edits and edit duplicate lists no longer trigger license changes

Just like tag edits, editing the duplicates list trigger a license change (or at least an indication):

As you can see in the entry below it, just closing it as a duplicate doesn't, so it's clearly a bug.

Answer 3

First of all thank you for this great piece of work, which fulfils a long standing debt to the community. I'm glad SE finally takes this licensing issue seriously.

As others mentioned before I too doubt that a very minor change warrants a license upgrade.

Changing a comma into a period in a written sentence definitely is very minor, and thus most likely doesn't classify as an adaptation of the original work. And as such wouldn't warrant it being licensed under the latest version of the license. The solution here would be to add some sort of minimum threshold. We all know that that doesn't deter users from posting a question, so why would the response here be any different.

On the other hand, changing a comma into a period within a code segment could have major implications for said code. It could be something that fixes or breaks the code entirely and therefore could be seen as an adaptation of the original. Which would warrant a change in license.

As there is no perfect way to classify the impact of an edit, I'd side with Yaakov here, and say that any edit should count, as that is the most practical solution.

Answer 4

I just wanted to give a pure, unadulterated THANK YOU for the incredible work on this.

I'm sure there are details and fine points to be picked over but as a community member I wanted to acknowledge this work that has been done & pushed live, as well as the announcement, the community engagement, etc. It's very appreciated.

Answer 5

Thank you for this. I'm glad this happened.

I still have concerns about how edits are handled, though. I find it odd that any edit - even the most minor ones - can cause a change in the license. I'm not entirely convinced that someone can take a CC BY-SA 2.5 or 3.0 post, fix one spelling mistake, and then release that under CC BY-SA 4.0.

I'm now OK with edits triggering a license upgrade between versions of a CC BY-SA license. At least in CC BY-SA 3.0, An adaptation can be released under "a Creative Commons jurisdiction license with the same License Elements as this License". Personally, I think it may be a stretch to consider the most minor edits an adaptation or derivative work, but there are also technological limitations if you tried to consider significance of edits.

I do hope that you allow a bulk upgrade of the license. Now that the concerns around the licensing have been resolved, I'd like to be able to make all of my content 4.0 and make sure that it is labeled as such.

status-completed

You can now see the license version number on the share popover

I would also suggest including the license information outside of the timeline. I think it should be visible on questions and answers, but perhaps it would be ok in the hover text around the attribution would be a good place, similar to how it is in the tooltip for the comment date. Also consider CC REL in the HTML markup for the page - this does support multiple licenses on the page and may provide hints to search engines and browsers as well.

Answer 6

bug status-review

What about tag wikis and excerpts? They are also (usually) contributed by users, and can be revised. However, at present there are no generally-accessible timelines for tag wikis (e.g., https://meta.stackexchange.com/posts/168600/timeline) or excerpts (e.g., https://meta.stackexchange.com/posts/168601/timeline). (There might be one visible to moderators, perhaps.) (At least, not on /posts/<id>/timeline.)

---

(I had a bit about making the timeline accessible, but turns out, that was status-completed this year: Add a link to the timeline of a post)

Answer 7

Prior to [May 2, 2018], the Terms of Service linked to CC BY-SA 3.0. On this date, the link changed to point to the 4.0 license. It was updated as part of a process that was not led by the Community team and there was no public announcement at time due to an internal disconnect at the time of the release.

I get it, an internal disconnect happened and the link got changed, and since it was in the Terms of Service, it took precedence over other notices on the site. This in turn impeded the Community Team from announcing the change in advance, and so when it was announced, it seemed abrupt.

However, I'd like some further elaboration in the section this text was contained in. Specifically, I'd like to see the following points addressed:

• How and why the link was changed in the first place
• Details about the internal disconnect, and why an announcement wasn't made about the change until September 2019
• Why there was no response to the questions raised at the time of the relicensing, not even a simple "we're working on a response" comment

Answer 8

Quick question:

3. The following tables available on [data.stackexchange.com][19] will include (in the next refresh) a ContentLicense field: Posts, PostHistory and Comments.

Will the new field be ContentLicense? Or will it be ContentLicenseId with a separate table for decoding? (The former feels rather un-SEDE-like, with the prevailing preference for the latter presumably doing lots for space efficiency.)

---

Seriously, though: huge props on this. The fact that this is the type of question sparked by the announcement is a big sign that you guys got it pretty much right. I still have quibbles on just why the 3.0-to-4.0 watershed is chosen in May '18 rather than September '19, but given that the rest is now in order there's really no point in those anymore.

Answer 9

What's the full status of SE's license to the content in the upcoming (and present and past) ToS?

As has been noted previously, some of the language in the ToS is unclear, and can be read as dual-licensing the post, with a global CC BY-SA license as well as a narrower SE-specific license to distribute (but (sometimes) not to allow others to redistribute) the content.

Can we ask you guys, as part of the current effort, to clarify that situation for both past content as well as (crucially) for what will come in the update to the licensing section of the ToS?

Answer 10

status-completed

Update: Rollbacks now revert the license version on the post to the version from the target rollback revision

You say a rollback can't introduce a license upgrade. But can rollbacks to an earlier revision downgrade the post (i.e. its currently visible content) to that older revision's license?

It's technically a new revision but it's the old revision's content with no new content added. (remark: I'd prefer that you can't downgrade the license in any way.)

Answer 11

Finally thank you. But there are still concerning questions:

• Why was the ToS being updated without legal oversight and/or why did your legal counsel not know how licensing works? This answer states they were at least by then "involved and on-board".
• Why was the initial feedback that retroactive re-licensing wouldn't work immediately ignored, then later dismissed? Despite the familiarity staff should have had from the MIT re-licensing plan.
• How will you ensure the above never happens again?

Answer 12

bug / feature-request status-completed

Update: Rollbacks now revert the license version on the post to the version from the target rollback revision

Roll-backs are meant to revert the license to the version that the rolled-back version was posted under. The language of the tool-tip suggests that a revision was created at 20:20, which corresponds with the most recent roll-back. In itself this isn't a revision of course.

In this case the tooltip should read: "CC License is based on the most recent post revision, which was made on May 12 at 11:55" (as that is the time of creation of Revision 2).

Answer 13

How will post dissociation requests work, since different license versions have different requirements for removing attribution?

For a while now, Stack Exchange has been processing dissociation (attribution removal) requests on all posts, regardless of whether they were edited (i.e. republished as an adaptation). From the signals I've picked up, it appears that this was mostly done just because the license required it and not because SE wanted to do it.

That post was published after the license change to 4.0, and the 4.0 license requires that attribution removal requests be processed on all contributions, including verbatim reproductions. However, the 3.0 license only requires dissociation upon request on adaptations (i.e. posts that were edited), and the 2.5 license doesn't require dissociation upon request at all.

How will SE handle post dissociation requests now that the license under which posts were made is now tracked, since it's only done as a formality required by the license? Will dissociation requests now be refused in cases where SE is not required to perform it (all 2.5 posts, and unedited 3.0 posts)? Or will they continue to be handled otherwise?

Answer 14

status-completed

A bit pedantic, but the comment timestamp tooltip has a superfluous space between the timestamp and the comma. And 'License' probably shouldn't be capitalized since it's not at the start of the list.

Answer 15

bug status-completed

Update: URL Rewriter updates (and others outlined above) no longer cause new licensed versions or post license version updates

Edits from the URL Rewriter Bot should probably be ignored. For example, this post¹.

Since this bot actually has a distinct username from the Community user, (which also handles things like anonymous edits) it should be easy to special-case. (Not sure if this was later changed, as other URL-edits seem to be done by the Community user.)

There are plenty of other examples of this happening.

_{¹Although this post is even worse since the edit is reverted (but not using a rollback) by Community a few days later.}

Answer 16

bug status-completed

The .relativetime (and .relativetime-clean) elements whose title attributes now show the date-based license do not get their text updated as time passes anymore.

We have elements like

<span title="2020-05-15 19:58:12Z , License: CC BY-SA 4.0" class="relativetime-clean">26 mins ago</span>

and JS of:

var date = prettyDate(spans[i].title);

function prettyDate(time) {
  if (time == null || time.length != 20) return;

The recently added License: part means that it's no longer 20 characters long, so for these elements, prettyDate doesn't return anything, and the text doesn't get updated.

Maybe change it to:

var date = prettyDate(spans[i].title.split(' , License:')[0]);

or something similar.

Answer 17

status-completed

Update: URL Rewriter updates (and others outlined above) no longer cause new licensed versions or post license version updates

Would have posted this as a comment, but I guess it warrants a full answer. IANAL, etc, disclaimer, disclaimer, but: to the best of my understanding, at least under United States copyright law, a "purely mechanical" modification of something (which pretty much by definition includes anything bot-driven, for example) does not create a new copyrightable work.

If I'm wrong about this, it is most likely a confusion with the "sweat of the brow" ruling from Feist Publications v. Rural Telephone Service, but it definitely seems like territory that warrants a consultation with the legal department if that hasn't already been addressed. If it has, great, but from several of the responses here it doesn't seem like the logic / opinion covering this is well publicized to the community?

Answer 18

Devil's advocate:

I dislike the 2.5 version of the license, because stuff, and want to use an old post under the newer 4.0 license. What is stopping me from making a "malicious" edit to upgrade the license version?

Or should I not be stopped at all?

Answer 19

Just to clarify the attribution requirements:

When a post has been revised, who should be credited as the "author?"

• Every time a piece of content on the site is edited, the editor creates a new version of the previous version. The new version of that work is considered to be republished and therefore governed under the CC BY-SA version in effect as of the day on which the edit was made.
• Each revision to a work creates a new version and is licensed separately. Thus current version of any piece of content (that appears on the site) is the most recent revision, and will have a license version based on the date on which that revision was published.

If "the editor creates a new version of the previous version" and the new version is "republished," it seems to imply that the revised post should be attributed only to the most recent editor. But if so, the original poster wouldn't receive any attribution.

Answer 20

feature-request status-declined

Please, show info about the comment license version in the timeline.

Answer 21

feature-request status-completed

You can now see the license version number on the share popover

It would be great if there was a setting or permanently to show the current license in the post metadata row under the title.

Answer 22

As someone who isn't really too concerned about licensing (I certainly don't care what use anyone makes of any content I've posted), I'm having trouble understanding how this applies in practice to reuse of code examples.

The stackoverflow.blog post "good coders borrow..." states "If you do copy code examples, please remember to provide attribution..."

How does this work for someone who searches for help, finds a code example on Stack Overflow without having created an account, and copies it? How is such a person even aware that the content is licensed?

Answer 23

For the most part, I think this is good news. I'm glad SE has taken this problem seriously and appreciate the effort to enable multiple licences for answers posted at different times.

But it seems strange and somewhat troubling that the smallest edit (fixing a bit of grammar, removing a redundant word here or there) can effectively relicense content that was offered on the understanding that an earlier licence applied.