Their email referenced AS3150 ... Here is what the (clearly frustrated) RamNode support person had to say last time I enquired: AS3150 is NTT, a large backbo

Their email referenced AS3150 ... Here is what the (clearly frustrated) RamNode support person had to say last time I enquired: AS3150 is NTT, a large backbone provider: https://bgp.he.net /AS3150 RamNode runs AS3842 and AS198203. We have contacted them before - they don't know why nor care why their system is raising issue with AS3150 in regard to emails from our network. But this issue isn't exclusive to our network either, and no other major email provider blocks emails like this. I have no reason not to believe him. :)