Possessives. Is there a rule in abbreviations?

Question

Please, which is the correct way to write the possessive form 's in abbreviations? I found these examples in two calendars:

January 19th - Martin Luther King Jr.'s Birthday.

January 19th - Martin Luther King Jr's., Birthday.

This is the first time that I see it. Please could somebody explain me about it?.

I'm even more confused with the comma in the last sentence.

Thanks in advance.

"the first time that I've seen" "could somebody explain it to me?" But really, I hate to correct you because you're always easy to understand. :) - Sabor, Jun 11, 2011

Answer 1

I took this from gfreed's link. (Please note the correct use of the apostraphe!) The things that hardly anybody ever knew! Fortunately, it doesn't make much difference to anybody except the PPPs (Proper Punctuation Police) fearsome Vigilante Patrol.

To form the plural of an abbreviation, a number, or a capital letter used as a noun, simply add an 's' to the end.

• A group of MPs
• The late 1940s
• Mind your Ps and Qs

To form the plural of an abbreviation with periods, a lowercase letter used as a noun, and abbreviations or capital letters that would be ambiguous or confusing if the 's' alone were added, use an apostrophe and an 's'.

• A group of M.P.'s
• The x's in the equation
• Sending SOS's"

apostrophe - 0074b507, Jun 11, 2011

And numbers, as in 1's and 2's. The rules have changed since I took English grammar lessons decades ago. Now you can also say 1s and 2s, group of M.P.s. English doesn't have something like the Real Academia that can clear any of these questions for us. - margaretcorwin, Jun 11, 2011

Oh and what really gets me is the bad mistake made by soooooooooo many people - signs outside their houses saying The Corwin's, The Bobbitt's, The Smith's, I see this everywhere. - margaretcorwin, Jun 11, 2011

My recommendation is to not get worked up over something like this. It's healthier. Language is a living thing... let it live! - Jeremias, Jun 11, 2011

Answer 2

I only see the first one being used.

Of course there are rules, but be careful. With abbreviations or acronyms you can be using 's to make plurals as well as to show possession.

Answer 3

I don't think the comma belongs there.

Jr.'s would be correct. The period in the abbreviation belongs to Jr. but the 's

belongs to the entire name.