It would only be at the "highest" level if were connected directly to a NAP. If it was connected through an InterNAP or via proxy with an ISP backbone, it would not have an entry amongst the internet routing table entries. (I don't think) Chris would probably know for sure. (I think) Maybe you could look on ARIN or IANA for a whitepaper.
A scapegoat is often as welcome as a solution...never memorize what you can look up.