When looking at a Wikipedia article, you suddenly spot something that looks like it may have been copied and pasted or closely paraphrased from elsewhere (typically from one or several of the sources), or it looks like a machine translation from some foreign text. What can you do?

If the entire article is a problem and any text that doesn't look like a copy-paste could not survive alone as an article:

• Click on the history tab and look at the earliest edit.
• If the article was started as a copy-paste and there's no permission or ownership asserted, nominate it for speedy deletion with {{db-copyvio|url=link to the source text}}
• If the article was started with different text, check to see if the copyvio was recently added. If it was, revert to a clean version.
  • You can put {{subst:cclean|url=link to the source text}} at the article's talk page to explain your action.
  • You can alert the editor who added it with {{subst:uw-copyvio|article}} at their talk page.
• If it looks like the copy-paste has been there for a while or if it's foundational copyvio (there since the article's creation), but there's reason to believe the person who added it here is the copyright owner, tag it for investigation with {{subst:copyvio|url=link to the source text}} and then look at the bottom right of the big boilerplate template that now replaces the article: it will contain two pre-set lines to copy-paste, one on today's listing on the Copyright Problems board, the other one on the article's creator or the person who most likely added the copyrighted content.

• Check the history. If the text was recently added, revert the article to a "clean" version or remove the text and place {{subst:cclean|url=link to the source text}} at the article's talk page to explain your action.
  • If you can identify the contributor, alert them by placing {{subst:uw-copyvio|article}} at their talk page.
• If appropriate request revision deletion of the reverted edits by adding {{copyvio-revdel}}
• If the text was not recently added or if the case is too complex for you to feel comfortable removing the violation, tag the article for investigation with {{subst:copyvio|url=link to the source text}} and then look at the bottom right of the big boilerplate template that now replaces the article: it will contain two pre-set lines to copy-paste, one on today's listing on the Copyright Problems board, the other one on the article's creator or the person who most likely added the copyrighted content (if you can tell who it was).

If you are a bit less in a hurry and the article has been tagged for investigation rather than speedy deletion, you can:

• Double-check the source. Look for a specific statement that it is public domain or has been licensed compatibly with CC-By-SA. If it has, you can attribute it or leave a link at the article's entry on the Copyright Problems board to the licensing statement so that somebody else can. Even if there isn't a specific statement, you can check against Wikipedia:Public domain to see if the content looks usable. If you aren't sure if it's usable, you can add a note of explanation at the Copyright Problems board listing for an administrator to evaluate.

• To save a bit of time: Creative commons has not declared compatibility with any software license (GPLv3 compatibility is one-way only). So unless the program itself is in the public domain, any text from the interface of a computer program is likely a copyright violation.

• Identify with what edit the dubious content has been copy-pasted, and mention that on the article's talk page and / or on the article's entry on the Copyright Problems board.
• Once you identify when the dubious content entered, check to see if other content entered at the same time or by the same contributor looks like a problem. If it seems like the copy-paste problem exists in only one part of the article, you can place the {{subst:copyvio|url=link to source}} template at the beginning of the problematic text and add a </div> at the end of the problematic text. If they added other text, you can check to see if you find other sources that have been copied.
• Check the talk page of the contributor who added the content. Are there other warnings? Consider whether it is appropriate to request a Contributor Copyright Investigation.
• You can also click on the link for temporary space and rewrite the problematic text. If you do, mention it on the article's talk page.

If the copyvio or the processes for handling them are unclear, you can do the same as above and the admins who work at the copyright problems board will address it.

• Copyvios might be unclear if:
  • The source has a license, but you are unsure if it is compatible. (Note that GFDL-only compatible texts imported before 1 November 2008 are acceptable, but texts from GFDL-only compatible sources imported on or after that date are not.)
  • The source may have copied from Wikipedia, but there is not enough evidence for you to decide that it is a {{backwardscopyvio}}.

If the copyvio only concerns a part of the article and has been added in a manner that it can be reverted to easily without also removing non-infringing content added in other parts of the article, handle this as though it were a Complete infringement (below).

If the copyvio only concerns a part of the article that cannot immediately be reverted to (because other parts of the article have been expanded in the meantime):

• Excise the copyvio
• Use the {{subst:cclean|url=link to source}} tag on the talk page to indicate that you did.
• Check to make sure that the contributor (if registered or recent IP) has been properly warned about the infringement and consider whether additional actions, such as a block or Contributor Copyright Investigation is necessary. (See Wikipedia:Copyright violations)
• Keep in mind that under the GFDL, the "network location" of revisions the current revision is based on has to date back four years.

• If the article has been rolled back to a version dated prior to 2020 September 02, and then additional copyvios are excised, no additional action needs to be taken to void the GFDL license, as the "network location" does not need to be preserved.
• Otherwise, {{CCBYSA4Source}} or {{CC-notice}} with parameter bysa4 must be placed in the 'References' section, to notify readers that the GFDL license is no longer valid. This is possible because section 3 of the CC BY-SA 4.0 license only requires a "URI or hyperlink to the Licensed Material to the extent reasonably practicable", without a requirement to preserve the "network location".

• If appropriate, request revision deletion of the reverted edits by adding {{copyvio-revdel}}.

Articles that seem to be complete infringements are handled in one of three ways:

• If the infringement is foundational copyvio (there since the article's creation) and there is no reason to believe that permission could be forthcoming:
  • process through speedy deletion in accordance with WP:CSD#G12
• If there is reason to believe that permission could be forthcoming (foundational or not):
  • Tag the article with {{subst:copyvio|url=link to the source text}}, list it at WP:CP and use the notification generated by the template to let the contributor know how to verify. It will be processed when permission arrives or, failing that, after a week.
• If the infringement is not foundational and there is no reason to believe that permission could be forthcoming:
  1. Revert the article to the last known good version with a relevant edit summary
  2. Recover any non-creative content you can (references, infoboxes, ELs, CATs and other)
  3. Enter the article's history
  4. Tick the checkbox for the last version before your revert
  5. Hold the shift key and tick the checkbox of the version where the copyvio was inserted
  6. Click the "Del / Undel Selected Revisions" button
  7. In the Revision Deletion interface, set "Hide revision text" to yes, and leave the rest untouched.
  8. Pick Criterion RD1
  9. Submit and exit.

Important note: Do not hide contributor names, in particular if you recover any content contributed by others, as you would otherwise infringe on their right to be attributed under the CC-BY-SA and GFDL licenses.

• A film stub has a 2-line lead and some cast information. Someone copy-pastes the synopsis from IMDB. After that, one or more editors create sections for production notes and reception, but the synopsis remains untouched. This is a safe case where you could revert back to the stub before the IMDB plot synopsis was added, then reintroduce the other sections (remember to credit the contributors in the edit summary), and revision delete.

• A lazier approach that violates the GFDL: Edit out the IMDB plot synopsis. Use {{CC-notice}} to link to the most recent edit with the copy-pasted synopsis, link the history page as the author(s), then revision delete from the recent edit back to the time the copy-pasted plot was added, inclusive.

• The same film stub gets the same synopsis, and the synopsis is then gradually expanded and partially rewritten, and only the first two paragraphs of the original material remain. This is a case where the original copyvio has led to an unauthorized derivative work, and you cannot delete the two remaining infringing paragraphs while retaining the rest of the synopsis - it remains "tainted" by the original copyvio.

• The derivative edits are dropped, and the page is reverted back a time before 2020 September 02, to a revision without any expansion of the synopsis. In this case, editing out the IMDB plot synopsis will not violate the GFDL, and therefore, {{CC-notice}} will not need to be added before revision deleting.

• Someone copy-pastes the synopsis from IMDB. It is caught quickly, and rolled back to the revision before the copy-pasting occurred. All subsequent revisions containing the copyvio are dropped and revision deleted.

• Since the most current revision is not based on any revision-deleted content, there is no need to preserve the "network location" of the deleted revisions. No GFDL violation has occurred, and therefore, {{CC-notice}} will not need to be added.

• Someone copy-pastes interface text from a permissively-licensed program.

• Unfortunately, Creative Commons has not declared compatibility with any software license, even with attribution-only licenses, like MIT or BSD. Unless the program is in the public domain, it should be revision-deleted.

Sounds too complex? Tag it with {{subst:copyvio|url=link to source}} instead; volunteers at WP:CP will deal with it.

Wikipedia has several tools that may be useful in checking for copyright problems.

• Earwig's Copyvio Detector will scan an article against the internet, excluding known mirrors (though not less common ones), and against its external links. It displays a percentage of text copied from the orginal source and highlights copies.
• The Duplication Detector will compare an article with another document, online or uploaded (including pdfs), looking for text string duplication.
• Wikiblame. Accessible under the "history" tab of every page on Wikipedia as "Revision history search", this tool can be useful in determining when a run of text first entered an article.
• User:Enterprisey/cv-revdel – Script to aid in tagging articles for revision deletion.
• There's a list of administrators willing to assist with copyvio work at Category:Wikipedia administrators willing to investigate copyright matters.

•  This article incorporates text by the Creative Commons available under the CC BY 4.0 license.