Moving the lower case "c" up above type in the last name McNeil? – english.stackexchange.com

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I believe this is because the name element (now) usually expressed "Mc" is actually an abbreviation for "Mac"; at one time, superscript (often with an underline or under dots) was a common way of writing abbreviations without resort to an apostrophe. This is preserved in the symbol № for "number".

You can see an example of this in the signature on the letter below, abbreviating "Nathaniel" (from Wikimedia Commons):



Writing Mc as M^C therefore preserves the original, "true" form of the name in a way that Mc does not (as it does not indicate the abbreviation).

There is also a discussion here about the aesthetic and legibility benefits of the superscript c, for more formal type-setting.