It is not a security (Jackson v Sterling Industries Ltd), nor a means to pressure a judgment debtor (Camdex International Ltd v Bank of Zambia (No. 2)), nor does it confer a proprietary interest in the assets of the judgment debtor (Cretanor Maritime Co Ltd v Irish Marine Management Ltd). However, some authorities have treated the Mareva injunction as an order to stop a judgment debtor from dissipating his assets so as to have the effect of frustrating judgment, rather than the more strenuous test of requiring an intent to abuse court procedure. An example of the former would be paying off a legitimate debt (Iraqi Ministry of Defence v Arcepey Shipping Co SA), whereas an example of the latter would be hiding the assets in overseas banks on receiving notice of the action.
It is recognised as being quite harsh on defendants because the order is often granted at the pre-trial stage in ex parte hearings, based on affidavit evidence alone. A Mareva injunction is often combined with an Anton Piller order in these circumstances. This can be disastrous for a defendant as the cumulative effect of these orders can be to destroy the whole of a business' custom by freezing most of its assets and revealing important information to its competitors.
A freezing order will usually only be made where the claimant can show that there was at least a good arguable case that they would succeed at trial and that the refusal of an injunction would involve a real risk that a judgment or award in their favour would remain unsatisfied (Ninemia Maritime corporation v Trave Schiffahrtgesellschaft m.b.H und Co.K.G [1983] 1 WLR 1412).