Scunthorpe problem

Scunthorpe problem

Company type	Phenomenon
Industry	Internet censorship, content filtering
Founded	April 1996
Headquarters	Scunthorpe , England

The Scunthorpe problem describes the accidental censorship of online material by spam filters or search engines when text contains letter sequences resembling offensive or inappropriate language. This phenomenon frequently impacts proper names, acronyms, and specialized terminology.

This issue occurs because automated systems can identify specific character strings but lack the cultural and contextual awareness to interpret their meaning accurately, resulting in overly broad filtering rules that cause false positives and block legitimate content.

Etymology and origin

The expression traces back to an event in April 1996 when AOL's profanity filter prevented users from the English town of Scunthorpe from accessing services due to the embedded substring "cunt" within the town’s name. In the early 2000s, Google’s optional SafeSearch feature similarly excluded local businesses and services referencing Scunthorpe in their names or URLs from search outcomes.

Workarounds

Addressing the Scunthorpe problem remains challenging because filters have difficulty discerning context precisely. A typical approach for businesses is to implement a whitelist containing known false positives, allowing legitimate terms with flagged substrings to bypass content restrictions.

Other examples

Instances where obscenity filters have made erroneous judgments include:

Denied domain registrations and account creations

• In April 1998, Jeff Gold was blocked from registering shitakemushrooms.com because the substring shit triggered an InterNIC filter designed to block "seven dirty words". (Shiitake refers to the edible mushroom Lentinula edodes.)
• In 2000, Canadian web filtering software blocked access to the Montreal Urban Community’s website since its French acronym CUM coincided with an English vulgar slang term.
• In February 2004, Craig Cockburn was unable to register his surname with Hotmail due to containing cock, a slang term for penis. Additionally, his job title referencing Cialis, a medication often flagged in spam filters, caused issues. Hotmail initially suggested altering his name to C0ckburn but later reversed the restriction. Similar problems arose in 2010 when he tried registering on the BBC website.
• In February 2006, Linda Callahan was initially barred from creating an email address including Allah on Yahoo!, though this ban was subsequently lifted.
• In July 2008, Herman I. Libshitz faced rejection from Verizon when trying to register an email address containing shit in his surname; Verizon later apologized for this refusal.

Restricted web searches

• Before January 1996, some searches for Super Bowl XXX were filtered because the Roman numeral "XXX" is commonly linked with pornography.
• Gareth Roelofse, designer of RomansInSussex.co.uk, observed in 2004 that numerous public networks blocked websites with "sex" in their domain names, hindering his educational site.
• In German, compound words occasionally include the substring sex through linking letters, triggering search engine filters—most notably in Staatsexamen.
• In 2008, Whakatāne in New Zealand experienced blocking of its name by a free wireless filter due to misinterpretation of "whak" as profanity; the town was eventually added to the filter’s whitelist.
• In July 2011, searches for Jiang were censored in China following rumors about former CCP leader Jiang Zemin’s death. Since "Jiang" (江) also means "river," queries related to rivers like the Yangtze were similarly blocked.
• In February 2018, after a policy update aimed at limiting weapons-related content, Google Shopping inadvertently prevented searches for products such as glue guns, Guns N' Roses, and Burgundy wine.

Emails blocked

• In 2001, Yahoo! Mail implemented an email filter designed to automatically alter JavaScript-related terms in HTML email to prevent script execution. This filter inserted hyphens into words such as "JavaScript", "JScript", "VBScript", and "LiveScript"; additionally, it substituted "eval", "mocha", and "expression" with "review", "espresso", and "statement," respectively. However, the replacements were applied indiscriminately, not confined to script code or word boundaries, resulting in errors like transforming medieval into medireview.
• In February 2003, a newly introduced spam filter blocked emails that mentioned the Sexual Offences Bill debated in the UK House of Commons, as well as messages connected to a Liberal Democrat censorship consultation. The filter also inadvertently blocked emails written in Welsh due to difficulties in recognizing the language.
• In October 2004, London's Horniman Museum failed to receive some emails because its name was mistakenly flagged by filters as a variation of the phrase "horny man."

Blocking due to ambiguous words

• In October 2004, email systems used by UK schools prevented messages promoting the pantomime Dick Whittington and His Cat because the name Dick is also slang for penis.
• In May 2006, emails expressing concerns about a planning application in Manchester were blocked because they contained the term erection, used in reference to building construction.
• The Winnipeg magazine The Beaver changed its name to Canada's History in 2010 after web filters obstructed its original title due to its sexual connotations, which limited its expansion. Publisher Deborah Morrison explained that the ambiguous nature of the name became problematic with increased Internet use.
• In June 2010, Twitter blocked a new user from Luxembourg only 29 minutes after tweeting about great tits (the bird species), despite including their Latin name Parus major; efforts to reverse the block were unsuccessful.
• In 2011, an email from a Dudley councillor was flagged for offensive language after referencing the Black Country dish faggots, a type of meatball but also a derogatory term.
• Residents of Penistone in South Yorkshire had their emails blocked because their town’s name contains the substring penis.
• People living in Clitheroe, Lancashire encountered repeated email filtering issues since their town’s name includes clit, an abbreviation for clitoris.
• Résumés containing Latin honors such as cum laude have been caught by spam filters due to the slang meaning of the word cum referring to semen.
• In March 2025, Reddit’s automated moderation flagged posts mentioning "Luigi," including those about the game Luigi's Mansion 3, because of associations with Luigi Mangione, who was suspected in the assassination of United Healthcare CEO Brian Thompson.

News coverage

• In June 2008, the news outlet OneNewsNow, operated by the anti-LGBT organization American Family Association, altered an Associated Press article about sprinter Tyson Gay, replacing "gay" with "homosexual", which resulted in his name appearing as "Tyson Homosexual". This same filter had previously changed basketball player Rudy Gay’s name to "Rudy Homosexual". Similarly, on the 70th anniversary of the atomic bombing of Hiroshima in 2015, the Observer Chronicle referred to the Enola Gay as the "Enola Homosexual".
• The sequence "ass" is sometimes replaced with "butt," leading to unintended substitutions such as "" for "classic", "" for "assignment", and "" for "assassinate". The phrase "clbuttic mistake"—a filtered version of "classic mistake"—is often cited online as an example of this kind of erroneous censorship known as the Scunthorpe problem.

Video games

• In 2008, Microsoft acknowledged that its filtering system, which blocked terms related to sexual orientation, mistakenly flagged Richard Gaywood's name as inappropriate. This prevented him from using it in his "gamertag" or "Real Name" field.
• In 2010, an Xbox Live user named Josh Moore was banned after indicating he resided in Fort Gay, West Virginia, as his profile was incorrectly judged offensive. Although he clarified the situation, Xbox initially upheld the suspension, causing him to miss a Call of Duty: Modern Warfare 2 competition. The ban was eventually overturned following an appeal by Mayor David Thompson and media coverage.
• The 2011 release of Pokémon Black and White featured Cofagrigus, which could not be traded online without assigning a nickname because its species name contained the sequence fag. Similar complications arose with Nosepass, Probopass, and Froslass due to substrings like ass. The trading system has since been updated to permit exchanges without requiring nicknames.
• In January 2014, some UK internet providers blocked files related to League of Legends because their filenames included the substring sex. This issue was subsequently resolved.

Other

• In 2013, file transfers labeled with the name of the Swedish city Falun triggered service disruptions at Diakrit, a company based in China. Diakrit addressed the problem by renaming these files. According to Fredrik Bergman of Diakrit, the interruptions were caused by the Great Firewall censoring terms associated with Falun Gong, a banned religious group in China.
• In November 2013, British users on Facebook experienced temporary blocks for using the term faggot when referring to the traditional food item.
• In May 2018, a cake order at grocery chain Publix was censored when the Latin phrase was partially removed, resulting in a cake that read "Summa --- Laude" despite explicit instructions.
• During May 2020, hashtags mentioning British political advisor Dominic Cummings failed to gain traction on Twitter because the substring cum activated an anti-pornography filter.
• In October 2020, words such as "bone", "pubic", and "stream" were blocked on a virtual platform hosting a paleontology conference.
• Facebook issued an apology in January 2021 after mistakenly flagging and muting users referencing the Devon landmark Plymouth Hoe, interpreting it as misogynistic content.
• In April 2021, Facebook removed the official page for the French town of Bitche. Officials responded by creating a new page under the postal code Mairie 57230. Facebook later reinstated the original page and apologized. As a precaution, authorities from nearby Rohrbach-lès-Bitche renamed their page to Ville de Rohrbach.
• In March 2025, the United States Department of Defense inadvertently deleted mentions of the Enola Gay aircraft during a purge targeting diversity, equity, and inclusion materials ordered by Defense Secretary Pete Hegseth. This was triggered by the presence of the substring gay.