To quote west79
: Hi, I would like to inform everybody that the European PSN Store version of Gran Turismo 5 Prologue has some serious issues about the terms of service user agreement.
First of all, for playing you need to have your PSN Account connected to the network like Warhawk, yes, it means you can't play it offline.
In other news the game can't be shared between different accounts. It's linked only to the PSN user that bought the game itself, while the license doesn't inform the user about this before buying, unlike Warhawk as you can see in this picture I took.
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