7.8 In Proper Names [XIII.43, 44]

The contractions for be, con, dis, and com are used in names containing an apostrophe, such as O'Connell. They are also used in names starting with Mc or Mac—as long as they constitute the first capitalized syllable following Mac or Mc and are not the last syllable of the name. Examples:

McConner MacCommack McBe
McBeman O'Connell O'Con-