"This one of a series of similar cases involving substantial sums ...... raises issues concerning the law of restitution and conspiracy which are not straight forward."
"The Second Claimant is the parent of a group of telecommunication companies. The First Claimant is a wholly owned subsidiary. Esprit Netherlands BV is another subsidiary in Holland. It also operates in Belgium. It is not a party to the action.
"Part of the overall charge paid by the user...... being payment for the content of the call passed by the network operator to the organisation or company providing the service."
"Part of the overall charge ...... being payment for the content of the call or other service delivered in the course of or as a direct consequence of the call..... passed on by the network operator, directly or indirectly to the service provider."
"the law requires that a mistake should have been made as to some existing fact...... It is prima facie unjust for the recipient to obtain the money when, if the payer had known the true state of affairs, he would not have paid."
"The state of mind of the payer must be related to the time when the payment was made. So also must the state of the facts or the law...... The point of the enquiry is to show that, had the payer known the true state of the facts or the law at that time, he would not have made the payment..... Proof that the alleged state of the facts at the time did not emerge until afterwards will usually be sufficient to show that there was, at the time of payment, no mistake."
"The essence of this principle is that it is unjust for a person to retain a benefit which he has received at the expense of another, without any legal ground to justify its retention, which that other person did not intend him to receive..... What, then, is the function of mistake in the field of restitution on the ground of unjust enrichment? .... A declaration of intention to confer the benefit, even if unenforceable, will be enough to justify the retention of the enrichment. A mistake, on the other hand, will be enough to justify the restitutionary remedy, on the ground that a benefit which cannot be legally justified should not be retained where it was a mistaken and thus unintended benefit."
"the first thing is to make a distinction between mistakes and mispredictions..... A mistake as to the future, a misprediction does not show that the plaintiff's judgment was visciated, only that as things turned out it was incorrectly exercised. A prediction is an exercise of judgment ....... If you then ..... complain of having been mistaken you are merely asking to be relieved of the risk knowingly run..... The safe course for one who does not want to bear the risk of disappointment which is inherent in predictions is to communicate with the recipient of the benefit in advance of finally committing it to him."
"...... a mere misprediction as to the future, exactly the kind of 'mistake' which you make when you clean my car believing, wrongly, that I will pay. A misprediction is nothing but the taking of a risk, an exercise of judgment which turns out badly rather than a judgment visciated. That is why the law requires mistakes to be both present or past fact."
"both mispredictions and mistakes of present fact do serve to demonstrate a non gratuitous intent ..... A trader who sends me goods which I have not asked for also has nothing to offer by way of negativing voluntariness; yet if I freely accept them I shall have to pay."
"The mistake which the tenants at will made, and which the House of Lords regarded as sufficient if the land owners had had knowledge of it, was no more than a misprediction: they believed that if they built they would be granted long leases; they knew they were all tenants at will for the present. This point was expressly considered by the Privy Council in Plimmer v Wellington Corporation . The opinion there expressed is that the House of Lords had not intended to limit the doctrine to mistakes of present fact as opposed to mistaken expectations. That must be right, for .... it would be obvious that, if you stand by and watch me building on your land and say nothing, my claim is just as good when the explanation of my conduct is that I believe that you will pay me or will grant me an interest in the land as it is when I believe I already have an interest. The reason is, that the ground for restitution here lies in your conduct, your standing by and letting me get into trouble. Inwards v Baker provides a modern example of a case in which equity responded even though the plaintiff merely mispredicted the future."
"The claimant alleges that the defendant discovered the error in 1998 and that thereafter they combined with others to buy up large numbers of pre-paid phone cards and made huge numbers of calls, which has resulted in an enormous amount of income to them, ...... and a substantial debit to the claimant..... The claimants allege a conspiracy. The defendants admit that neither statute nor common law provides a remedy for a claimant against defendants in such circumstances, even if proved. As at present I see respectable argument in favour of such a submission, but I am not persuaded that it is bound to succeed."
"This type of problem is no doubt on the increase with the advance of computers. It has given rise to a fair amount of consideration in the Law Commission. Taking away the element of conspiracy, one considers the situation of an individual who goes to a cash dispensing machine and asks for£50 and is given£500 . Four days later he asks his bank for his statement and he sees that he has only been debited with£50 . Thereafter he returns to the cash dispensing machine, makes ten separate requests for£50 and receives ten times£500 . Those are the sorts of cases where the law, which was developed in the last century and the early part of this century, was not really designed to deal with because it was not a problem which commerce had to cope with at that time."