How should we handle unattributed copying?
As long as it is possible to bring compliance with the licence of the original, we should do this, i.e. reference to to the original place (btw. reference should always be given, even if the licence does not require so. That is just part of having good manners).
Where the licence cannot be complied with, or the copying is not allowed, obviously the violating text (or images) must be removed. However, it should be possible to describe a little in one's own words what it is about and link to it.
We shouldn't allow copying of text from external sites for a bunch of reasons:
External sites (such as the Ubuntu support wikis) are maintained, and will be updated when new releases come out. A copied answer will fall out of sync.
Linking to an external site improves its page rank and will allow Ubuntu users who don't visit StackExchange to find the original answer more easily.
We should give credit to the original author(s).
I suggest that when an answer is shown to be copied from an external site, we do one of two things:
If the answer is properly attributed, a moderator should remove the text and replace it with a link to the original page.
If the answer is not properly attributed, a moderator should remove the answer.
I think completely removing an answer is an extreme - How can we tell if it's blatantly copied without attribution if they don't mention the source? In that case we can't do much. If a moderator is able to tell that it was copied from a source they should by then know the source and be able to edit the answer to keep it up to standards.
Furthermore if a user catches it they can flag an answer and mention the source it was copied from. I really find it disturbing to remove an entire answer just because of a formatting issue. If the content is correct linking a source is merely a formatting issue IMO (I take copyrighting seriously, but others may not). Furthermore having a copy of the text with a link to the main is not a bad idea.
- This can help cut down the reading of an entire article to the bare essentials.
- Like you said sources change text for one version may be overwritten when a new version comes out, etc. Maintaining a quoted text and a link is the best course of action IMO - It gives the user the text they need and the option to go read more.
I agree that plagiarism is clearly unacceptable. Further, we can not permit people to copy (with or without attribution) large amounts (beyond plausible fair use) of non-free content. That would both put us in legal jeopardy and compromise this site's free nature.
But limited quoting with attribution is always acceptable. Further, in some cases, it may be appropriate to reuse a significant amount of content, provided we comply with the original license (incl. attribution), and it is compatible with ours. This site is also a wiki, and we can also update answers. Even if it weren't, it would be reasonable to have a fixed extract of a changeable external page. After all, printed matter does this all the time.