Well, like GP said, it depends what is meant by "backdoor." Laws requiring data to be turned over to governmental parties, and in some cases gagging anyone from saying it happened, seems like exactly the function of "backdoor" even if it doesn't take the form of a master password the NSA has or something.

So long as a company can be compelled to do this in secrecy, their assurances about "no backdoor", "no direct access", "we process every request ourselves" are basically meaningless, since not even they have control over their customers' privacy (if they comply with law.)