Excellent list. For completion's sake, I'd include intentional typos as an instance of category 5. This can be hard to catch if the typo is in a name. A logic

Excellent list. For completion's sake, I'd include intentional typos as an instance of category 5. This can be hard to catch if the typo is in a name. A logical extension of that would be entirely made-up names for non-essential people/places. At the age of 5, Hawking visited Oxford, incidentally passing through Fakenamingham-on-Watermarkshire. Dictionaries/encyclopedias have been known to insert entirely fake entries as a way of proving ownership.(http://articles.chicagotribune.com/2005-09-21/features/0509200275_1_electronic-dictionary-new-oxford-american-dictionary-new-yorker http://articles.chicagotribune.com/2005-09-21/features/05092...) In the age of ebooks and print-on-demand, those could be tailored to the individual licensee.