I just rejected a Suggested Edit for a tag wiki, for copied content. The issue, and source of my question, is that it was copied from gaming.SE's tag wiki for the game. Looking at the copyright license that SE sites are under indicates they require attribution when copying content. The edit didn't have attribution, but it is also on a SE site, so it's copying content from themselves.
Is this a copyright violation, or not?
Yes, this is a copyright violation. The holder of the copyright is the author of the content, not Stack Exchange. Stack Exchange is only redistributing content which they have a right to redistribute but do not own.
All user content is licensed to SE by its author with a license (CC BY-SA) that requires attribution, and is licensed by SE to site viewers under that same license.
Think of it this way: if I copy your answer without attribution, is it ok as long as I'm only using your work in another Stack Exchange answer? No? Well then. Copyright law does protect you here.
Now in practice, this isn't a big deal. There is no visible author attribution for a tag wiki (unlike for questions and answers where the main author is prominently visible when viewing the post normally). So you don't have to clutter the tag wiki with an author attribution just to credit Stack Exchange contributors. It would be acceptable to have the attribution in the edit comment, which is visible whenever one views the list of authors of the tag wiki (viz, the tag wiki's revision history).
In principle, you should credit all authors and link to their Arqade profile. In practice, when do that, I tend to only leave a link to the original tag wiki, which is a lot simpler. This is technically wrong because the other tag could be deleted, or the tag wiki could be included in a dump that doesn't include the original site.
This is a problem for the initial content because you can't have an edit comment. Make some cosmetic edit and write a comment on the second revision, I guess.
It's actually rare that the same tag wiki is appropriate on two sites. Different communities tend to require different information. Often, the other site's content is a good source of information but needs to be both filtered for community relevance and expanded for community relevance.
It's actually rare that the same tag wiki is appropriate on two sites.
Commented
Feb 27, 2013 at 0:09
Whatever the legal requirements, I think there is a moral obligation to attribute the source, even under these circumstances.
That said, I think users should be encouraged to write content in their own words, and, hopefully, enforcing the attribution will encourage them to do so rather than admitting "stolen from [here]".
I will answer slightly off-topic, since there's nothing much to add on-topic to existing excellent answers.
Leaving aside the issue of copyright and attribution, if you are literally copy/pasting the content of tag wiki from one site to another, your tag wiki content is likely wrong!
Why?
Because tag wiki content is meant to clearly explain not simply what the term means (heck, we can point to Wikipedia for that on most tags), but to explain what kinds of questions should be tagged with this tag, and what is the relationship of this topic to SFF site.
While I admittedly don't always follow this guidline for my tag wiki posts, here is an example of SFF-specific tag Wikis:
This tag can be used for 2 distinct purposes:
More specifically, for questions related to the movie "2012" released in 2009.
Generally, for questions related to any events happening in SFF works in the year 2012 A.D.
This year is not infrequently mentioned in SFF, due to end-of-the-world-in-2012-12-21--due-to-Mayan-calendar-ending-in-2012 predictions (the above movie obviously is based on the same idea).
However, "Mayan End of the World" is not the only possible topic related to 2012. For example, 2012 features in a series of essays/letters written in 1987 by famous SciFi writers at the request of L. Ron Hubbard about the world in 2012.
As Kevin points out, you have a moral obligation to attribute the source of your cross-source. However, it's more than just a moral obligation, it's also a requirement of the CC-BY-SA. (look at the bottom right of every single SE page for the square logo and a link to the appropriate CC terms).
There's no mechanical enforcement, but that's where community moderation comes into play. In a perfect world nobody would copy without providing source, of course ;-) This applies to all content, anywhere, anytime.
So, as a site policy, it needs to be established that if you cross-copy content from anywhere, and you don't reword it into your own words, then you must cite the source. If you don't, then you've just committed plagiarism and that's bad.
The habit I get into is using the quote function of the post editor and providing the URL at the end of my quote. That way everyone can tell that I intend this text to be set off from all the rest of my post, and nobody is confused as to what I mean. An example follows:
You are free:
- to Share — to copy, distribute and transmit the work
- to Remix — to adapt the work
- to make commercial use of the work
Under the following conditions:
- Attribution — You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). ....
It's not a novel, it's a short paragraph that, if we're lucky, has reasonable grammar, punctuation, and decently summarizes the topic. I reject all claims of copyright on those I've "authored". They are public domain, and anyone is free to re-use them. Please, if they're good enough to use on another SE site, go for it.
