In Germany the banking industry has lost at least 2 high profile cases in the highest civil court in the recent years.
They are not allowed to change the terms of business without the customer actively accepting the change. This seems the most applicable case here. I guess such fee was not at all in their terms before, so just sending an email that now there is won't work.
Another case that loans must not have handling fees (on top of interest) might be less applicable here.
There was also a case affecting all businesses many years ago. A debt does not expire earlier than 10 years later. So if the business still owns the customer something, they can't just say, oh sorry it has expired earlier. This affects mostly gift certificates or prepaid phone subscriptions, but why not "inactive" money at Paypal.
They are not allowed to change the terms of business without the customer actively accepting the change. This seems the most applicable case here. I guess such fee was not at all in their terms before, so just sending an email that now there is won't work.
Another case that loans must not have handling fees (on top of interest) might be less applicable here.
There was also a case affecting all businesses many years ago. A debt does not expire earlier than 10 years later. So if the business still owns the customer something, they can't just say, oh sorry it has expired earlier. This affects mostly gift certificates or prepaid phone subscriptions, but why not "inactive" money at Paypal.