Manufactures vs. Manufacturers
A question from the Peanut Gallery always makes my day. John asks:
“I have a question for you. In many documents like inspection requirements and vendor data requirements, I often see the word: Manufactures, as in Manufactures Data Book requirements. I always thought it should be Manufacturers. Are both correct, or do they have different meanings?”
Your thoughts are correct, John. They do have different meanings.
“Manufactures” is a verb (present tense).
Example: Cameron manufactures blowout preventers.
“Manufacturers” is a noun (plural).
Cameron and National Oilwell Varco are manufacturers of blowout preventers.
They are often pronounced the same, especially with a Texas drawl.
In the example you gave, if somebody “manufactures” data book requirements, the boss needs to have a serious talk with that person.
If you are referencing the data book requirements provided by a single manufacturer, it should be the singular possessive: manufacturer’s data book.
If you are referencing the data book requirements provided by multiple manufacturers, it should be the plural possessive: manufacturers’ data books.