I thought that if there was more than 1 backorder the domain goes to a private GoDaddy auction
That's what I thought too but apparently not if the backorders were placed at two different GoDaddy owned companies and/or resellers.
I still have the reply to my email (rec'd Sep 18th 2009). The domain in question was successfully captured by GoDaddy or one of their shell registrars they use for drop catching and subsequently moved to a GoDaddy account:
Dear Sir/Madam:
Thank you for contacting online support
Our system checks the registry twice a day. Domains are released at 3pm EST and consequently available for re-registration - in the event that a specific domain is backordered through multiple companies, both companies are likely to win the domain so it becomes a โtoss of the coinโ situation when both attempt to register the domain at the same time. This works the same way as any other domain registration - essentially if it is released,
our Domain Alert Pro Backorder service is just as likely to win the domain as any other backorder system (NOT TRUE - lol).
Please understand that a backorder does not guarantee that you will acquire the domain name being backordered. The domain name you are backordering may be renewed by the current registrant and not become available or we may be unsuccessful in our attempts to grab it and register it on your behalf.
Please note that if your backorder is not successful, it can be reassigned to another domain name.
Sincerely,
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Well, I knew this was a canned response or bs so I called them. When pressed, they conceded it is possible to backorder the same name at two or more GoDaddy owned companies or GoDaddy resellers and the domain is allocated at random in this instance. Not sure what would happen if the domain was backordered by two or more people at the same reseller. Presumably then there would be an auction.
Bear in mind this was almost two years ago. Procedures may have changed in the meantime.