If memory serves, I think TPB is somehow related to iPredator [1][2], though I'm not sure if that is the case anymore. This may give them _lots_ of experience running VPN software, which would be usable if that is indeed how they're communicating between VPS providers.

[1] https://www.ipredator.se/ [2] http://torrentfreak.com/pirate-bay-announces-ipredator-globa...

Why would they use a VPN provider? It's trivial to set up your own if you control the systems at both ends.

To make the legal side effects "Somebody Else's Problem"? seeing as that's the service many VPN providers offer. Might save them having to get new load balancer VPS quite so often, making it that much harder and more time consuming to knock offline.

I don't know, that's why I'm asking though.

Assuming at least one side isn't under a NAT, true. Otherwise it gets... "fun".

Why would you be under a NAT? A public IP and a networking allotment is one of the core offerings of almost every cloud provider out there.

A NAT does not stop you if you do it right. Console games have been hosting servers through NATs for the last decade.

I would speculate that the massive advertising revenue generated by the 'bay probably renders any such 'fun' factor trivial.