A backdoor is a mechanism for someone to be given access to an internal system, or internal data. In the case of data being "pushed", it most certainly could be done so, and the same statement would remain true.

If your comment was true, you would also assume data handed directly to authorities in criminal cases where subpoena's are issued would also be ruled out, but we know that information is handed out to authorities as required by law under subpoena.

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.)