When it comes to proofreading copy, whether it’s intended to be published online or in print, there’s no room for error. As soon as that copy is out in the public domain, it stands as a representation of whoever has written it.

The job of a proofreader is to act as a safety net for these errors, catching and modifying mistakes before they can be allowed to slip through – but sometimes, mistakes slip through regardless. Even the most diminutive of proofreading errors can cause huge repercussions, at the very least making the author seem careless and uninformed, and at the worst changing the meaning of what is being said entirely.

Although this can be amusing in some circumstances, ultimately this casts a bright light on just why proofreading is so important to your business.

Read on for ten of my favourite famous proofreading gaffes, where small instances of poor proofreading have gone on to cause widespread chagrin for the red-faced authors.

1. Proofreaders wanted

When posting an advert looking for proofreaders, you would expect the job description to be grammatically flawless. However, a job advert posted recently seeking a ‘Copy Editor for Women’s Magazine Site’ contained no less than 3 spelling errors: twice asking for ‘editting’ experience, and going on to cite the name of the magazine incorrectly as ‘Women’s World’ instead of ‘Woman’s World’.

2. Continuity error

Of course, it isn’t only orthographical gaffes that need to be picked up on by the proofreader – maintaining continuity is just as important. An early edition of Mary Shelley’s Frankenstein contains the phrase ‘the latter days of December’. However, a vigilant proofreader would have altered this to ‘September’, which was the month being referred to in the rest of the passage. Later editions of the novel carried the correct date.

3. Grauniad or Guardian?

The Guardian newspaper has garnered an impressive reputation for frequent typographical errors, so much so that it has earned the nickname ‘The Grauniad’ (first used in Private Eye magazine). Often cited is The Guardian’s first ever issue, which contained the spelling error ‘atction’ for ‘auction’.

4. Mis-stated

In 1988 the University of Wisconsin awarded thousands of diplomas with the glaring error ‘Wisconson’ typed on every one. Six months passed before anyone picked up on this blunder. An official at the time defended this by saying the certificates had been proofread, but only to check their names and degree-subjects – not any of the ‘standard information’.

5. When corrections become errors

A poem by W.B. Yeats, ‘Among School Children’, contained a reference to the ‘solider Aristotle’. An over-zealous printer assumed the poet had made a spelling error and corrected it to ‘soldier Aristotle’ – a correction that stayed in print for years and gave the sentence an entirely different meaning.

6. Adulterated text

In the 1632 edition of the King James Bible the omission of the word ‘not’ gave whole new meaning to the seventh commandment, appearing as ‘Thou shalt commit adultery’. The printer of this error was fined £300 for his mistake.

7. Web figures gone awry

Several products at Comet’s online store were advertised at bargain prices in 2002, when some obviously incorrect figures were left unnoticed and went live on the site. This resulted in some lucky shoppers being able to buy, for example, an Aiwa hi-fi worth £89 for £8.43.

8. The costly comma

The case of a comma cost a Canadian cable television provider over a million dollars in 2006, when it lost a court case in a contract dispute with a telephone company. This was due to the inclusion of the second comma in the line of the contract which stated that the agreement “shall continue in force for a period of five years from the date it is made, and thereafter for successive five year terms, unless and until terminated by one year prior notice in writing by either party.”

Though the cable television company believed that the first five years of the deal were secured, the inclusion of the second comma changed the meaning of the sentence, which allowed the telephone company to terminate the contract at any time with one year’s notice.

9. Checking failure

GCSE students across England were left in the lurch in 2008, when their exam papers contained a significant disparity between question and answer booklets. The exam board responsible for the papers had failed to pick up on this and allowed some hundred thousand exam booklets to be printed before school invigilators noticed the mistake.

10. Not consulting a dictionary

A newspaper headline touting the benefits of reading Webster’s Dictionary in 2000 can hardly have done much for the Jackson Citizen Patriot’s credibility. The published story about an avid reader of the famous dictionary was accompanied by the headline: ‘Want to spell like a champ? Read Wenster’s dictionary.’