Scunthorpe problem

The Scunthorpe problem is the blocking of emails, forum posts or search results by a spam filter or search engine because words in their text contain a string of letters that are shared with an obscene word or one that is considered improper or inadmissible for other reasons. While computers can easily identify strings of text within a document, broad blocking rules may result in false positives, causing innocent phrases to be blocked.

The problem was named after an incident in 1996 in which AOL's profanity filter prevented residents of the town of Scunthorpe, Lincolnshire, England, from creating accounts with AOL, because the town's name contains the substring cunt. Years later, Google's filters apparently made the same mistake, preventing residents from searching for local businesses that included Scunthorpe in their names.

Mistaken decisions by obscenity filters include:

Some websites have anti-obscenity filters which automatically replace offensive content with words intended to be equivalent in meaning.

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