timppu: Also, you sidestepped my original analogy. It may be the person in question has bought a valid ticket, but has just temporarily misplaced it. So there can be false positives too, but if you feel that is the case, then you don't have to pay.
bazilisek: That's a very different type of false positive. There's enormous difference between "oh, I actually had a ticket, here it is" and "oh, I actually didn't download the game, here it… isn't". Good luck proving the latter.
You don't have to. They have to prove in court you pirated/shared it.
And in the ticket analogy, you can still get false positives, e.g. you bought a single ticket from a machine, but dropped it to street. How do you prove you had bought the ticket?
bazilisek: EDIT: Or, to rephrase, if you are caught by a ticket inspector on the bus, that's no false positive – you clearly and demonstrably were on the bus.
It is still a false positive, if you still had bought a ticket, but have misplaced it. Their intention is not to fine you for 80€ for not having the ticket with you, but for trying to ride the bus for free. That's why there's the process of claim for rectification.
Yet, it may also be you end up paying for a false positive too, like you had bought a single ticket, but someone stole it from you.
An old anecdote I read from a Finnish magazine a long time ago (claimed to be a true story that the column writer saw himself, but who knows for real, I wouldn't be surprised a similar anecdote is told elsewhere too):
A young punk rocker boy was riding a subway, and a cranky old lady was sitting opposite to him. The lady started cussing at the boy for how he looks, how the youngsters are good for nothing, break things etc. etc. The boy just tried to keep his cool and disregard the old lady.
On one station, the ticket inspectors come in and demand everyone to present their tickets. The old lady takes hers from the purse and holds it in the air victoriously. Suddenly the punk rocker boy snatches the lady's ticket, and swallows it.
The lady loses it and starts screaming: "The boy ate it! The boy ate my ticket! Did everyone see? The boy took it!". But rest of the passengers remained silent (including the writer of the column), for reasons unknown. Either they didn't see it, or didn't want to side with the cranky old lady.
The ticket inspectors approach the lady and the boy, and ask him whether that is true. The boy looks amazed and denies having done anything like that, which makes the lady lose it even more. In the end, the screaming lady is lead out of the subway, and the ride continues.
True or false, I don't know. But could happen.