apostrophe possessive
The mark that shows ownership.
Add ’s to a singular noun, even one that already ends in s: the boss’s desk, James’s book, Jesus’s name, Socrates’s trial. Add only an apostrophe to a regular plural that already ends in s: the bosses’ desks, the Joneses’ house. Joint ownership takes one mark on the last name: Maria and Tom’s apartment. Separate ownership takes a mark on each: Maria’s and Tom’s apartments.
Examples
UseJames’s report is late.
UseJesus’s parables
Usethe teachers’ lounge
Avoidthe teacher’s lounge (If more than one teacher shares it.)
UseLuis and Ana’s lease
News and magazines often drop the second s after any singular name that already ends in s: James’, Socrates’, the boss’ desk. Older print does the same. The above is our guidance.