Possessives standing alone (solitary possessives)
Sometimes the noun a possessive modifies is not expressed, but is implied or understood. Form the possessive as though the noun were included.
You can probably get this filled at your doctor's (office).
We're invited to the Smith's (house) for dinner.
Retain possessive form of company names as appropriate.
Wear an old shirt and Levi's (jeans).
Do not confuse singular plural with possessive.
We've been invited to the Smith's (house) for dinner.
We've always enjoyed dinner at the Smiths.
The people themselves are being referenced and therefore there is no possessive.
If the construction is awkward or creates confusion, it is acceptable to recast the sentence.
You can probably get this filled at your doctor's office.
OR
You can probably get this filled by your doctor.
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