Some interesting semantics going on here. When I first saw the headline, I thought 'What?!?' I mean, a subpoena is a court order, signed by a judge, commanding you to appear in court and/or produce certain evidence. How can Google just 'reject' such an order? (They can't.) What they can do -- and, apparently, what they are doing -- is _appeal_ against the order.
This is perhaps just sloppiness on the part of the Reuters reporter and laxity in his sub-editor(s). But then, in the remainder of the article, this fast-and-loose use of terminology continues. Some examples:
I suppose that 'demand' and 'compel' are connotatively similar, as perhaps are 'bid', 'request' and 'motion'. The last time I checked, however, 'request' and 'demand' meant rather different things. These terms can't be mixed up, higgledy-piggledy, just to avoid repetition -- like a student with a thesaurus.