Make sure you have a good reason for the check. It will only be accepted to counter vandalism or disruption to Wikimedia wikis. Valid reasons include needing a block of the underlying IP or IP range, disruptive sockpuppetry, vote-stacking, and similar disruption where the technical evidence from running a check would prevent or reduce further disruption.
Be specific in your reasons. Ambiguous or insufficient reasons will cause delays. Explain the disruption and why you believe the accounts are related, ideally using diff links or other evidence.
Make sure there are no local checkusers or policies.
Reason(s): I've assumed that this user is sock-puppet of previously blocked user Nj.K.V. User Rtava has same interest, same articles (about Bosnian medieval royalty), even grammar errors are the same as user Nj.K.V. He is making so called sneaky vandalism putting false statements in various articles and inventing proofs for those claims. --C3r4 (talk) 19:49, 23 October 2013 (UTC)
As an administrator at bs.wiki I second this. -- Edinwiki (talk) 12:26, 25 October 2013 (UTC)
Proofs? In bs.wikipedia one proof was questioned: "Ban Kulin, son of ban Borić". But I show it in a Google ebook: "Banus Culinus, Borichii filius" in Latin means "Ban Kulin son of ban Borić" in English, so I didn't invent it. Second, the blocked user never mentioned this or any other references I used. Rtava (talk) 12:55, 25 October 2013 (UTC)
Inconclusive as no comparative data available. Though I do note that there are two unused accounts created on the same IP and other similarities. Leaving them at the moment. — billinghurstsDrewth 04:03, 27 October 2013 (UTC)
I was specifically asked was one of the other accounts Ideabeach. It is. Personally, I don't count them as socks until used, hence why I didn't specify the account, though when asked, it is appropriate to confirm the check. — billinghurstsDrewth 15:04, 27 October 2013 (UTC)
Thank you for your answer. It was very helpful.--C3r4 (talk) 18:30, 27 October 2013 (UTC)
== Checking == Hi Billinghurst, thank you for your check here. As you said: (there are) two unused accounts created on the same IP and other similarities, is that means that those accounts which are you checked are made from the same IP address and what exactly means other similarities. That user which is perhaps the same as user on en.wiki Ideabeach. I have no clue who to proof this, nor is my field of interest medieval history (on bs.wiki I rather writing about chemistry, geography etc.) but I have some clues that this person falsifying history making himself as descendant of Bosnian royal family (there is also private web page and facebook group but it's irrelevant to the subject). There were similar case back in February 2010 where user:Amsal@bs.wiki had battle at the same subject but then user:NJ.K.V. (as you said similar but not quit sock-puppet of nowadays user:Rtava) is blocked 'cause of other vandalism and inappropriate behavior. Just answer me what to do and is there any rule or any procedure to make this sneaky vandal stopped. Best regards--C3r4 (talk) 14:37, 27 October 2013 (UTC)
Following your question about a specific account, I have updated the CU commentary. It is a bit of a situation of chicken and egg to get increased CU surveillance,, however, if there are ongoing and specific issues of long term abuse (vandalism and suspected sockpuppetry), then in a language of your choice, we need to have written a lucid narrative of the issue. I feel that we are currently snapping at flies, which makes it hard to do checkuser, and to get stewards to start recording a case. At this stage, stewards are not maintaining cases of long term for bswiki, and that is probably due to that missing narrative, and once that is created then the stewards have the meta archives, and our private archives where non-public detailed data can be maintained. [Note: Stewards are reticent to keep non-public data unless there is a demonstrated reason that it should be maintained, and it sounds as though we are approaching that from your above explanation] — billinghurstsDrewth 15:14, 27 October 2013 (UTC)
Hi Billinghurst. I would like to request that you record a case, since the user continues with disruptive editing on bs.wiki. In the following I can summarize a few details that might be usable. You stated that Ideabeach is another account that was used by the same person (or at least from the same IP address). Ideabeach was blocked for disruptive editing and personal attacks against various admins. He also used another sockpuppet Reaubilya which was also blocked for similar behavior, and if I remember correctly was also suspected to be a sockpuppet. It is no coincidence that all these accounts, including bs:User:Rtava, have vandalized the same (and/or similar) pages, mostly about en:Ban Borić (bs:Ban Borić) and topics related to the Bosnian royal family. If we look at the dates of the contributios we see that Reaubilya has started editing at 6th of October and was finally blocked around the 15th of October. Ideabeach started editing at June 22nd, and was blocked around 15th of october. It is no surprise that on the 17th of October the user started editing with a new account Rtava on the 17th of October, after receiving an indefinite block on en.wiki. From the edits we can also see many similarities if we look at the changes of the article Ban Borić: bs.wiki and en.wiki. These changes have been reverted on en.wiki because the user used original sources and the proposed changes did not receive any consensus. The same story applies for the articles on bs.wiki, including previously seen personal attacks on other users but also revert wars.
I personally see enough reasons for a block, but it would probably be better to do this globally but also to record a case so that this user can be identified more easily in the future. -- Edinwiki (talk) 09:29, 29 October 2013 (UTC)
Update: Because the user continued with personal attacks against other users I had no other choice than to block him indefinitely. However, like I said, it might still be useful to record a case for possible future abuses. Regards. Edinwiki (talk) 14:44, 29 October 2013 (UTC)
I'd like to write some introduction to this case. It's back to February 2010 (as I mentioned), but even before that date there were same case on en.wikipedia when multiple sockpuppets found. After his block on en.wikipedia, he's moved on bs.wikipedia with same intentions. Whole discussion was on several pages here some of them: Wikipedia:Čaršija/Arhiva_22#Ja_ne_znam_.C5.A1ta_da_radim..., Razgovor_sa_korisnikom:Nj.K.V. and even here. After some turbulent days and discussion, he's finally blocked due abuse and violent behavior. Nowadays, it took five days until I realized that is something wrong with this new user Rtava. After I made some comments, I decided to write above to CU. Most of his edits could be identified as original research, and finally reverted. It could be some leftovers but it will be cleaned in normally wikipedia editing process.--C3r4 (talk) 10:07, 31 October 2013 (UTC)
Deferred to have an admin or bureaucrat confirm the request, and further explain the purpose of CU request.—The preceding unsigned comment was added byBillinghurst (talk • contribs) 04:09 27 October 2013 (UTC).
Not done no follow up, closing as insufficient need demonstrated by wiki. Please lodge a new request by admin or bureaucrat if required. — billinghurstsDrewth 12:24, 13 November 2013 (UTC)
Reason(s): Globally locked user Lacberto trying to bypass the lock. See also the history of zh-yue:成在基, zh-yue:男性連帶 and zh-yue:姜義錫, in which the users listed here continue to add poorly translated (possibly machine translation) contents to the page.--William915 (talk) 06:04, 27 October 2013 (UTC)
What would checkuser be useful for, when you already established this on behavioural evidence? Please simply block such users. --MF-W 14:28, 27 October 2013 (UTC)
Actually I want to have those sock puppet accounts globally locked as well, for which I think more evidence is needed.--William915 (talk) 02:28, 28 October 2013 (UTC)
Some of these accounts have significant number of contributions on other projects and therefore are not suitable candidates for global lock. On the other hand, global account Pangal does not exist. Ruslik (talk) 19:00, 28 October 2013 (UTC)
Just check and lock(if applicable) Iedomeneo then.--William915 (talk) 02:37, 29 October 2013 (UTC)
Not done Sounds retributive, not issue management. Sounds like this is account management at a local level, and is not a global issue. Please note that most sock policies are local policy implementations (there is no global policy about general multiple accounts for a user). — billinghurstsDrewth 11:52, 30 October 2013 (UTC)
Reason(s): Two reliable users expressed their strong opinion that Respeto, Borg and Nordmann were sock puppets. These three accounts did recently vote in a poll. Clarity would be very helpful here. --Kronf (talk) 22:21, 1 November 2013 (UTC)
Confirmed Respeto, Borg (local only), Cheflektorin, Nuzák, Nordmann (local only), Bedsten, BS-USB. — billinghurstsDrewth 06:51, 2 November 2013 (UTC)
Reason(s): I am admin on en WV and I want to request a CU on a team of socks. There has been many heated debate regarding whether users 1 and 2 are the same person. There is much reason to doubt the same, as has been documented by various admins in the debate. I strongly suspect user 3 as sock of user 1 as well because of very similar behaviour and same editing style and editing area/interest. User 3 knows everything about whats been going on wiki lately even though xe recently joined us. User 1 was blocked on wiki for a short period for disruptive editing, and block discussion can be found here. User 1 was previously blocked on Wikipedia back in 2008. --Saqib (talk) 10:01, 23 November 2013 (UTC)
I personally believe there's grounds for a check, though I doubt that sufficient evidence has been presented above. Both the first two users have been blocked on en.wikipedia for socking, but back in 2008. Let me see if we can present better evidence for running a check. --Rschen7754 10:14, 23 November 2013 (UTC)
Back in 2008, the top two accounts were confirmed to be sockpuppets on en-wiki (there's some leeway as it seems Alice was a legitimate alt-account due to threats supposedly received as part of a very contentious topic area (Northern Ireland/"The Troubles", however, the two later tag teamed in the area. SirFozzie (talk) 11:25, 23 November 2013 (UTC)
Bedu Mumtaz = Neotarf, I don't know it that's already known.
118.93nzp has been blocked several times as an anon, you may guess something just having a look at its name.
Those accounts are unrelated by CU (though W.Frank and Alice share something which is currently shared by ~10% of computers), I must underline they never edited at the same time nor the same day. If we had a sockpuppeteer steward, well, it would likely behave and being seen by CU the like them.
MmeLePetomaine is the "most unrelated" one.
Inconclusive--Vituzzu (talk) 12:50, 23 November 2013 (UTC)
Vituzzu: I apologise for coming late to the party, but I have only just become aware of this discussion.
Are you saying that my account is unrelated to any of the others you checked or just that it is inconclusive?
I'm afraid I don't understand your comment: "If we had a sockpuppeteer steward, well, it would likely behave and being seen by CU the like them." May I trouble you to clarify and explain this comment, please?
Is there a reason that you left out the other accounts that were specifically asked to be checked here?
Why were the accounts that were most linked by their peculiar interests and editing patterns (User:Peterfitzgerald, User:Cjensen, User:Ypsilon, User:SpendrupsForAll, User:MmeLePetomaine) omitted? --118.93nzp (talk) 00:23, 24 November 2013 (UTC)
Because no evidence was provided to check those accounts. We can't just ask for accounts to be checked when we feel like it, CheckUser is not for fishing. --Rschen7754 00:25, 24 November 2013 (UTC)
Reason(s): All of the mentioned users share the same area of interest on some historical articles (Alexander the Great, Mohammad Reza Pahlavi, Xerxes II). They attempt to deceive or mislead other editors, disrupt discussions and distort consensus. They use multiple accounts to create an illusion of support and they contribute to the same page or discussion with multiple accounts:
Trying to deceive and mislead editors by changing "خشایارشای دوم"transliterated as "Khashayarsha-ye dovvom" to "خشایارشا دوم"transliterated as "Khashayarsha dovvom" by one account and making the opposite by another account: (Ali4984, Ali4984, Ali4984, Ali4984, Mahsa87, Mahsa87, and Mahsa87)
Reason(s): I think (wp:duck)the owner of this username is user:پارسا آملی (global blocked troll with lots of sockpuppets in fa.wiki, en.wiki, commons &... ) after last blocking in fa wiki he made new sockpuppet with same edits on the articles. Please checking this user name (Roya_hamidinejhad) and tell me other sockpuppets. Thanks alot MehdiTalk 19:13, 26 November 2013 (UTC)
It does not appear that you have linked to the ostensible sockmaster's account above. Please list which accounts for which you believe you have local fawiki evidence of sockpuppetry. Note that having multiple accounts on one project does not mean that violations occurred on other projects. Furthermore, the Wikimedia Commons has its own CUs and issues need to be addressed first locally. Thank you. -- Avi (talk) 20:53, 2 December 2013 (UTC)
Reason(s): These all were engaging in similar editing (unauthorized bot tasks of similar kinds). It is against the local alternate accounts policy to evade the block of one account using a sock, but we're not 100% sure that they are the same.--Jasper Deng (talk) 07:54, 1 December 2013 (UTC)
The accounts that I could check are confirmed to each other. --Bsadowski1 (talk) 08:16, 1 December 2013 (UTC)
Are there any other accounts?--GZWDer (talk) 08:58, 1 December 2013 (UTC)
There is one legitimate user operating the accounts. They will be contacted privately. --Bsadowski1 (talk) 10:34, 1 December 2013 (UTC)
I'm not trying to be antagonistic, but why isn't that information being released now? The user operating these accounts is in violation of our sockpuppetry policy, and of our bot policy, and should be held accountable. I'm not saying that person needs to be blocked, but the Wikidata community has the right to decide what to do with them. — PinkAmpers&(Je vous invite à me parler) 17:18, 1 December 2013 (UTC)
Bsadowski1 may not be at liberty to release the details because of the user's local privacy laws.--Jasper Deng (talk) 01:50, 3 December 2013 (UTC)
This sounds like bogus. --MF-W 21:00, 3 December 2013 (UTC)
If so, then why not reveal the account?--Jasper Deng (talk) 02:29, 4 December 2013 (UTC)
Where there is uncertainty the stewards are expected to act more conservatively and on this case at this time you should respect our judgement on the matter. The primary account is not being abused, and you have been notified of all secondary accounts, and it is my understanding that one of the stewards is doing follow-up om the matter. The matter is ongoing for stewards. Have some trust people. — billinghurstsDrewth 11:54, 4 December 2013 (UTC)
I don't think anyone wasn't having trust here, billinghurst. We've all got bits of our own, and know how annoying it can be to be needlessly second-guessed. Rschen, Jasper, and myself just asked for some clarification after Bsadowski skirted over a fairly significant point. None of us was saying y'all need to throw someone to the pitchforks straight away, if you think more good can be done for now by talking privately. Now, given another week or so, I think it's reasonable for us to expect either a disclosure of the username to the local community, or a thorough explanation of why this will not be done; but this was just a procedural question, which I thank you for now answering. — PinkAmpers&(Je vous invite à me parler) 10:56, 7 December 2013 (UTC)