Forming compound possessives of nouns.

Today we answer a question from a loyal reader:

Dear Scribe,

A problem has long vexed me!  When adding a possessive to more than one person or entity in a sentence, which names include an “apostrophe s”?  For example, would I say “Bob and Tony’s agreement” or “Bob’s and Tony’s agreement”?  Is it “Tom, Dick, and Harry’s vacation” or “Tom’s, Dick’s, and Harry’s vacation”?  I have always applied the “apostrophe s” to just the last person listed, as it sounds the way that people speak.  But I’m starting to see variations out there.

Sincerely,

Vexed in Portland

Dear Vexed,

As your question implies, forming compound possessives (also known as joint possessives) seems tricky.  But fortunately, there’s a simple rule: if two or more nouns share ownership of something together, then only add “apostrophe s” to the last noun, e.g.,

• After its founding in 1983, Dave and Barrie’s firm quickly boomed.  [This shows that Dave and Barrie shared ownership of a booming law firm.]

• Madeleine and Amelia’s cat tree is in the living room.  [This shows that Madeleine and Amelia jointly own the cat tree.  (Although that may be debatable at times.)]

But if two or more nouns possess something separately, add “apostrophe s” to both nouns, e.g.,

• Chad’s and Stephen’s karaoke singing was memorable.  [This shows that Chad and Stephen had separate, and “memorable,” karaoke singing.]

• Molly’s and Kathryn’s masterful brief each received effusive praise from the judge.  [This shows that Molly and Kathryn each wrote a masterful brief.  (Of course they did!)]

See, forming compound possessives is easy.  And fun!

That is all for now …