Q. How do you pluralize given names such as in brand names? For example, I was editing a book where a person received a gift of a pair of Jimmy Choo shoes. Another character exclaimed, “You could miss my birthday too if it means a pair of Jimmys.” An apostrophe is not quite right since it is not possessive. And using the “ie” form of plural with a “y” would look odd IMO. What’s the best way to handle it?

A. The plural form of a name is normally formed by adding either “s” or “es” (no apostrophe), so we would recommend “Jimmys.” See CMOS 7.9, which includes “Harrys” among its examples.

But considering the subject, you’d be wise also to consider the usage in Lauren Weisberger’s best-selling The Devil Wears Prada (New York: Broadway Books, 2004):

“Jeffy, bring me a pair of Jimmy’s in a size . . .” (p. 104; ellipsis in original)

Some stylebooks recommend an apostrophe for certain plurals—for example, to join an “s” to a number or an abbreviation (as in “1900’s” or “BA’s”). And for brand names, we’re all more or less familiar with possessive stand-alone forms like Ben & Jerry’s. So “Jimmy’s” is a reasonable choice.

But aside from this one instance in Weisberger’s otherwise influential book, we find no convincing evidence for such a preference. Elsewhere in the book, the shoes are referred to as “Jimmy Choos” (no apostrophe; see pp. 6 and 52), and that seems to be the most common usage IRL.