h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I would like to hear an explanation of the difference between "our bank's branches" and "our bank branches"
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That's a good one!

Our bank's branches:

The apostrophe before the s indicates that there is only one bank. So it means "the branches belonging to our bank".

Our bank branches:

This could mean that our branch does something, namely, it branches (in the way that a tree does). But treating it like the first phrase, the lack of any s suggests that "bank branches" is a phrase, so it means:

The bank branches belonging to us.

Now whether that means the same as "The branches belonging to our bank" is a matter for debate.

Not sure about this. When I google "bank branches" I get about 1,140,000 entries as opposed to 46,000 with "bank's branches". The one with the apostrophe seems to be along the lines you mention emphasizing the branches belonging to this particular bank, i.e. "some of the bank's branches, one of the bank's branches, each of the bank's branches" (some of the banks listed are foreign so that may mean NNS usage). The one without apostrophe seems to have a much wider use meaning branches of the/a bank. Does that make any sense?

That makes perfect sense. It's like "dog hair" as opposed to "dog's hair". My dog's hair is rough and white, but my house is covered in dog hair.

Thanks...this is from a NNS of English (Spanish speaker) who wrote in an offer of services to a client... "our bank's branch in your offices" for a service they are offering to companies to set up all of their services in a kind of "branch" on site in the company to take care of all the financial needs of the company and its employees. According to what we have said then this would be a correct usage. What do you think?

That's correct.

Thanks