Scunthorpe problem

The Scunthorpe problem is the unintentional blocking of websites, e-mails, forum posts or search results by a spam filter or search engine because their text contains a string of letters that appear to have an obscene or otherwise unacceptable meaning. Names, abbreviations, and technical terms are most often cited as being affected by the issue.

An example of the Scunthorpe problem in Wikipedia because of a regular expression match

The problem arises since computers can easily identify strings of text within a document, but interpreting words of this kind requires considerable ability to interpret a wide range of contexts, possibly across many cultures, which is an extremely difficult task. As a result, broad blocking rules may result in false positives affecting innocent phrases.

Origin and historyEdit

The problem was named after an incident in 1996 in which AOL's profanity filter prevented residents of the town of Scunthorpe, North Lincolnshire, England, from creating accounts with AOL, because the town's name contains the substring "cunt".[1] In the early 2000s Google's opt-in SafeSearch filters apparently made the same mistake, preventing people from searching for local businesses or URLs that included Scunthorpe in their names.[2]

Other examplesEdit

Mistaken decisions by obscenity filters include:

Refused web domain names and account registrationsEdit

  • In April 1998, Jeff Gold attempted to register the domain name, but due to the substring shit he was blocked by an InterNIC filter prohibiting the "seven dirty words" which was active between 1996 and the transfer of control to ICANN in 1998.[3] (Shitake is from the Japanese name for the edible fungus Lentinula edodes.)
  • In 2000, a Canadian television news story on web filtering software found that the website for the Montreal Urban Community (Communauté urbaine de Montréal, in French) was entirely blocked because its domain name was its French acronym CUM (;[4] "cum" (among other meanings) is English-language slang for semen.
  • In February 2004 in Scotland, Craig Cockburn reported that he was unable to use his surname (pronounced "Coburn") with Hotmail. Separately he had problems with his workplace email because his job title, software specialist, contained the substring Cialis, an erectile dysfunction medication commonly included in spam e-mails. Hotmail initially told him to spell his name C0ckburn (with a zero instead of the letter "o"), but later reversed the ban.[5] In 2010 he had a similar problem registering on the BBC website, where again the first four characters of his surname caused a problem for the content filter.[6]
  • In February 2006, Linda Callahan was initially prevented from registering her name with Yahoo! as an e-mail address as it contained the substring Allah. Yahoo! later reversed the ban.[7]
  • In July 2008, Dr. Herman I. Libshitz could not register an e-mail address containing his name from Verizon because his surname contained the substring shit, and Verizon initially rejected his request for an exception. In a subsequent statement, a Verizon spokeswoman apologized for not approving his desired e-mail address.[8]
  • In August 2018, Natalie Weiner reported on social media that she was unable to create an account for herself on a website, because her last name is also a word used as slang for penis. It was reported that "hundreds" of people replied saying this affected them as well. Names of those replying included Ben Schmuck (last name is a Yiddish word for "penis"), and Arun Dikshit (last name is Sanskrit for one who teaches or provides knowledge, containing the substring shit).[9][10][11] Articles covering this stated that it was a common and extremely difficult technical problem for which no robust solution was currently available.[9]

Blocked web searchesEdit

  • In the months leading up to January 1996, some web searches for Super Bowl XXX were being filtered, because the Roman numeral for the game and the site (XXX) is also used to identify pornography.[12]
  • Gareth Roelofse, the web designer for, noted in 2004, "We found many library Net stations, school networks and Internet cafes block sites with the word 'sex' in the domain name. This was a challenge for because its target audience is school children."[2]
  • In 2008, the filter of the free wireless service of the town of Whakatane in New Zealand blocked searches involving the town's own name because the filter's phonetic analysis deemed the "whak" to sound like fuck; the town name is in Maori, and in the Maori language "wh" is most commonly pronounced as "f". The town subsequently put the town name on the filter's whitelist.[13]
  • In July 2011, web searches in China on the name Jiang were blocked following claims on the Sina Weibo microblogging site that former Chinese Communist Party general secretary Jiang Zemin had died. Since the word "Jiang" meaning "river" is written with the same Chinese character (江), searches related to rivers including the Yangtze (Cháng Jiāng) produced the message "According to the relevant laws, regulations and policies, the results of this search cannot be displayed."[14]
  • In February 2018, web searches on Google's shopping platform were blocked for items such as glue guns, Guns N' Roses, and Burgundy after Google hastily patched its search system that was displaying results for weapons and accessories that violated Google's stated policies.[15]

Blocked emailsEdit

  • In 2001, Yahoo! Mail introduced an email filter which automatically replaced JavaScript-related strings with alternative versions, to prevent the possibility of JavaScript viruses in HTML email. The filter would hyphenate the terms "Javascript", "Jscript", "Vbscript" and "Livescript"; and replaced "eval", "mocha" and "expression" with the similar but not quite synonymous terms "review", "espresso" and "statement", respectively. Assumptions were involved in the writing of the filters: no attempts were made to limit these string replacements to script sections and attributes, or to respect word boundaries, in case this would leave some loopholes open. This resulted in such errors as medireview in place of medieval.[16][17][18]
  • In February 2003, Members of Parliament at the British House of Commons found that a new spam filter was blocking e-mails to them. It blocked e-mails containing references to the Sexual Offences Bill then under debate, as well as some messages relating to a Liberal Democrat consultation paper on censorship.[19] It also blocked e-mails sent in Welsh because it did not recognise the language.[20]
  • In October 2004, it was reported that the Horniman Museum in London was failing to receive some of its e-mail because filters mistakenly treated its name as a version of the words horny man. Horny is a common slang term for sexual arousal.[21]
  • Problems can occur with the words socialism, socialist, and specialist because they contain the substring Cialis. Blocking of the word specialist is liable to block emailed résumés and curricula vitarum and other material including job descriptions.[22]

Blocked for words with two meaningsEdit

  • In October 2004, e-mails advertising the pantomime Dick Whittington sent by a teacher from Norwich in the UK were blocked by school computers because of the use of the name Dick, sometimes used as slang for penis.[23]
  • In May 2006, a man in Manchester in the UK found that e-mails he wrote to his local council to complain about a planning application had been blocked as they contained the word erection when referring to a structure.[24]
  • Blocked e-mails and web searches relating to The Beaver, a magazine based in Winnipeg, caused the publisher to change its name to Canada's History in 2010, after 89 years of publication.[25] Publisher Deborah Morrison commented: "Back in 1920, The Beaver was a perfectly appropriate name. And while its other meaning [vulva] is nothing new, its ambiguity began to pose a whole new challenge with the advance of the Internet. The name became an impediment to our growth".[26]
  • In June 2010, Twitter blocked a user from Luxembourg 29 minutes after he had opened his account and posted his first tweet. The tweet read 'Finally! A pair of great tits (Parus major) has moved into my birdhouse!’. Despite including the Latin name to point out that the tweet was about birds, any attempts to unblock the account were in vain.[27]
  • In 2011, a councillor in Dudley found an email flagged for profanity by his council's security software after mentioning the Black Country dish, faggots (a type of meatball, but also a derogatory term for a homosexual).[28]
  • Residents of Penistone in South Yorkshire have had e-mails blocked because the town's name includes the substring penis.[29]
  • Lightwater in Surrey suffered similarly because its name contains the substring twat.
  • Residents of Clitheroe (Lancashire, England) have been repeatedly inconvenienced because their town's name includes the substring clit, which is short for "clitoris".[30]
  • Résumés of magna cum laude graduates have been blocked by spam filters because of inclusion of the word cum, which is Latin for with (in this usage), but is sometimes used as slang for semen in English usage.[31]

News articles damagedEdit

  • In June 2008, a news site run by the American Family Association filtered an Associated Press article on sprinter Tyson Gay, replacing instances of "gay" with "homosexual", thus rendering his name as "Tyson Homosexual".[32]
  • The word or string "ass" may be replaced by "butt", resulting in "clbuttic" for "classic" and "buttbuttinate" for "assassinate".[33]


  • In November 2013, British Facebook temporarily blocked users for using the word faggot in reference to the dish faggot.[34]
  • In January 2014, files used in the online game League of Legends were reported as being blocked by some UK ISP filters due to the names 'VarusExpirationTimer.luaobj' and 'XerathMageChainsExtended.luaobj' containing the letters used in the word "sex".[35]
  • In May 2018, the website of the grocery store Publix would not allow a cake to be ordered containing the Latin phrase summa cum laude. The customer attempted to rectify the problem by including special instructions but still ended up with a cake reading "Summa --- Laude".[36][37]
  • In May 2020, despite extensive media scrutiny, some hashtags directly referring to British political advisor Dominic Cummings were unable to trend on Twitter because the substring cum in Cummings' surname triggered Twitter's anti-porn filter.[38]
  • In October 2020 a profanity filter banned the word 'bone' at a paleontology conference[39]

See alsoEdit


  1. ^ Clive Feather (25 April 1996). Peter G. Neumann (ed.). "AOL censors British town's name!". The Risks Digest.
  2. ^ a b Declan McCullagh (23 April 2004). "Google's chastity belt too tight". CNET. Archived from the original on 16 June 2011.
  3. ^ Paul Festa (27 April 1998). "Food domain found "obscene"".
  4. ^ "Foire aux questions". Archived from the original on 21 October 2012. Retrieved 24 February 2011.
  5. ^ Barker, Garry (26 February 2004). "How Mr C0ckburn fought spam". The Sydney Morning Herald. Archived from the original on 3 September 2009.
  6. ^ Cockburn, Craig (9 March 2010). "BBC fail – my correct name is not permitted".
  7. ^ "Is Yahoo Banning Allah?". Kallahar's Place. Archived from the original on 14 January 2016. Retrieved 24 February 2011.
  8. ^ "When your name gets turned against you". Archived from the original on 5 August 2008. Retrieved 3 August 2008.
  9. ^ a b "The 'Scunthorpe Problem' Has Never Really Been Solved - Slashdot".
  10. ^ Weiner, Natalie (28 August 2018). "this is without a doubt the best thing that's ever happened to".
  11. ^ "Twitter / Account Suspended".
  12. ^ "E-Rate And Filtering: A Review Of The Children's Internet Protection Act". Congressional Hearings. General. Energy and Commerce, Subcommittee on Telecommunications and the Internet. 4 April 2001.
  13. ^ "F-Word Town's Name Gets Censored By Internet Filter". Archived from the original on 1 December 2008. Retrieved 27 July 2011.CS1 maint: BOT: original-url status unknown (link)
  14. ^ Chin, Josh (6 July 2011). "Following Jiang Death Rumors, China's Rivers Go Missing". The Wall Street Journal.
  15. ^ "Wine lovers cannot buy Burgundy tipple on Google as internet giant cracks down on 'gun' searches". Archived from the original on 2 March 2018. Retrieved 27 February 2018.
  16. ^ "Yahoo admits mangling e-mail". BBC News. 19 July 2002. Retrieved 21 June 2013.
  17. ^ "Hard news". Need To Know 2002-07-12. 12 July 2002. Retrieved 21 June 2013.
  18. ^ Knight, Will (15 July 2002). "Email security filter spawns new words". New Scientist. Retrieved 21 June 2013.
  19. ^ BBC E-mail vetting blocks MPs' sex debate 4 February 2003
  20. ^ BBC Software blocks MPs' Welsh e-mail 5 February 2003
  21. ^ Kwintner, Adrian (5 October 2004). "Name of museum is confused with porn". News Shopper.
  22. ^ "Comment headaches". The Peking Duck. 21 November 2004.
  23. ^ Sam Jones Panto email falls foul of filth filter The Guardian 14 October 2004
  24. ^ BBC E-mail filter blocks 'erection' 30 May 2006
  25. ^ "Canada's The Beaver magazine renamed to end porn mix-up". Agence France-Presse. 12 January 2010. Archived from the original on 5 March 2014.
  26. ^ Sheerin, Jude (29 March 2010). "How spam filters dictated Canadian magazine's fate". BBC News.
  27. ^ "Luxemburger Twitter-Neubenutzer nach 29 Minuten blockiert". Tageblatt. 22 June 2010. Retrieved 12 June 2010.
  28. ^ "Black Country Councillor Caught up in Faggots Farce". Birmingham Mail. 24 February 2011.
  29. ^ Tom Chatfield (17 April 2013). "The 10 best words the internet has given English". the Guardian.
  30. ^ Keyes, Ralph (2010). Unmentionables: From Family Jewels to Friendly Fire – What We Say Instead of What We Mean. John Murray. ISBN 978-1-84854-456-7.
  31. ^ Maher, Kris. "Don't Let Spam Filters Snatch Your Resume". Career Journal. Archived from the original on 23 October 2006. Retrieved 11 February 2008.
  32. ^ Frauenfelder, Mark (30 June 2008). "Homophobic news site changes athlete Tyson Gay to Tyson Homosexual". BoingBoing.
  33. ^ Moore, Matthew (2 September 2008). "The Clbuttic Mistake: When obscenity filters go wrong". The Daily Telegraph. London.
  34. ^ "Faggots and peas fall foul of Facebook censors". Express and Star. November 2013.
  35. ^ Gibbs, Samuel (21 January 2014). "UK porn filter blocks game update that contained 'sex'". The Guardian. London.
  36. ^ Ferguson, Amber (22 May 2018). "Proud mom orders 'Summa Cum Laude' cake online. Publix censors it: Summa … Laude". The Washington Post. ISSN 0190-8286. Retrieved 22 May 2018.
  37. ^ Amatulli, Jenna (22 May 2018). "Publix Censors Teen's 'Summa Cum Laude' Graduation Cake". Huffington post.
  38. ^ Hern, Alex (27 May 2020). "Anti Porn filters stop Dominic Cummings trending on twitter". The Guardian.
  39. ^ Ferreira, Becky (15 October 2020). "A Profanity Filter Banned the Word 'Bone' at a Paleontology Conference".

External linksEdit