The court said that actual and punitive damages weren't warranted in such a case, but that a kind of statutorily defined penalty of €100 did apply. (The term is Abmahnung, which seems to be a sort of compulsory penalty that doesn't require a court case to be levied.)
Update: A commenter who knows more than I do (that's why we like comments) explains that the fee is a "civil pre-trial settlement to avoid a costly civil trial if the facts are clear."
The court said, "Private individuals can't be held responsible for compensation or punitive damages when a third party makes use of an unprotected wireless LAN access point for copyright violation."
The decision is welcome in Germany, because it removes a lot of worry about unlimited fees (such as have been levied only directly against filesharers in the US), and the fees that can be collected are small enough that the various copyright holders may not pursue them.
Nonetheless, the precedent now allows these fees to be collected, and that does change the equation.
Germans thus warned ought to enable any kind of encryption. The linked article notes that even WEP, though it's easily broken, would qualify because then the third party would have to break into the network (a fairly severe crime in Germany since 2007), making the access point's owner not liable.
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