Norwich, Anton Piller and Mareva orders: Relief for extraordinary circumstances

Law360 Canada (November 3, 2026, 2:02 PM EST) --

Adin Wagner

In estate litigation, clients often come with a sense of urgency seeking to collect relevant information, documentation and assets. They might need to see a copy of a will that is being withheld unjustifiably. They may suspect that a once joint investment account is being drained by a nefarious sibling. Ultimately, they want to know about and have access to absolutely everything to understand the scale of the estate and to ensure that it does not slip away. There are court orders that can assist with that.

Norwich, Anton Piller and Mareva orders are peripheral to the ordinary litigation process. They constitute extraordinary relief and powerful tools of preservation and discovery. As such, they are generally limited to circumstances which, if left unaddressed, risk defeating the very purpose of the litigation itself. Put another way, courts will hesitate to grant these orders absent a level of necessity and urgency that would justify the circumvention of the ordinary litigation process.

Norwich order: Discovery

A Norwich order is an equitable remedy that, in certain extraordinary circumstances, allows for a claimant or potential claimant to obtain discovery from a third party prior to an action being commenced. The vagueness of this definition is consistent with the remedy’s discretionary and flexible nature. As the Court of Appeal for Ontario stated in GEA Group AG v. Ventra Group Co., 2009, 96 O.R. (3d) 481, while many of the general principles applicable in Ontario are well-developed, “the nature and scope of the Norwich … principle is far from settled.”

That said, Canadian courts have identified the following circumstances where a Norwich order could be justified:

1. to identify wrongdoers;
2. to find and preserve evidence of a wrongdoing or even to determine whether an action exists; and
3. to trace and preserve assets.

As a tool of pre-action discovery, Norwich orders can be used to identify details about both the wrongdoer and the wrong done to solidify a potential claim. The practical application to estate litigation is obvious. Once appointed, an estate trustee immediately seizes control over assets that often do not belong entirely or at all to them. If they move quickly enough, an estate trustee can siphon off estate assets before the beneficiaries have a chance to pursue their litigation rights. A Norwich order may be the answer. Motions for Norwich orders are often brought ex parte and combined with a Mareva injunction to prevent dissipation or misappropriation of funds pending trial.

Fundamentally, the decision to grant a Norwich order is a question of necessity and fairness, as manifested in the following test:

1. the plaintiff must have a bona fide claim or potential claim against a wrongdoer;
2. the person against whom the Norwich order is sought must have a connection to the wrong beyond being a witness to it;
3. the person against whom the Norwich order is sought must be the only practical source of the needed information;
4. the party seeking the disclosure must compensate the person against whom the Norwich order is sought for all expenses arising out of the discovery; and
5. the interests of justice must favour obtaining the information.

At first glance, there appears to be some overlap between Norwich relief and certain discovery rights under the Rules of Civil Procedure, most specifically production from non-parties under Rule 30.10. The court has noted this as well. GEA Group AG clarifies that a Norwich order is not intended “to serve as a substitute for the normal discovery regime” nor “as a device to circumvent the normal discovery process.” But the Rules’ dominion over the normal discovery process should not be taken to mean that Norwich orders are not available or cannot be obtained. Rather, the two bases for relief operate in concert, with Norwich relief filling out the pre-action space under certain circumstances, and the Rules covering anything interlocutory.

Anton Piller order: Civil search and seizure

An Anton Piller order is a form of injunctive relief that authorizes a private party to compel entrance to the premises of a target to conduct a surprise search, the purpose of which is to seize and preserve evidence to further its claim in a private dispute. The primary goal of an Anton Piller-type order is to prevent the target from frustrating the moving party’s right to a fair trial.

Say, for example, just before he passed away, the deceased wrote out a last will and testament leaving everything to his niece. After the deceased died, his widow told the niece that if she dares to try and collect on the estate, she will burn the only copy of the last will and testament. A successful ex parte motion for an Anton Piller order may enable the niece to seize the handwritten will before this seminal piece of evidence is destroyed.

There are four essential conditions to obtain such an order, as laid out by the Supreme Court of Canada in Celanese Canada Inc. v. Murray Demolition Corp., 2006 SCC 36. First, the moving party must demonstrate a strong prima facie case. Second, the damage to the moving party of the responding party’s alleged misconduct, potential or actual, must be very serious. Third, there must be convincing evidence that the responding party has in its possession incriminating documents or things, and fourthly it must be shown that there is a real possibility that the defendant may destroy such material before the discovery process can do its work.

Without a doubt, Anton Piller orders are an exceptional remedy of a “draconian nature” that “should only be granted in the clearest of circumstances.” The potential for abuse helps explain the high barrier to entry as well as the repeated warnings to diligently safeguard the privacy of the order target (to the degree possible). The courts are very prescriptive in that regard. Helpfully, the Commercial List provides a model order to be tailored to suit the particular circumstances of each case.

Mareva injunction: Freeze orders

A Mareva injunction is an interlocutory order restraining a defendant/respondent from disposing of or dealing with assets prior to trial. As with the Anton Piller order, the commercial list provides a model order for a Mareva injunction.

This remedy pulls opposite to the common law resistance to granting execution before judgment. As explained by the SCC in Aetna Financial Services Ltd. v. Feigelman, [1985] 1 S.C.R. 2:


Usually, a Mareva injunction is sought ex parte. After all, stealth is the whole point — to pre-empt any action by the defendant to remove assets from the jurisdiction.

To obtain a Mareva injunction, a plaintiff must satisfy the normal criteria for an injunction and also several additional criteria. For a Mareva injunction, the moving party must establish: (i) a strong prima facie case; (ii) that the defendant has assets in the jurisdiction; and (iii) that there is a serious risk that the defendant will remove property or dissipate assets before the judgment.

As with the other forms of relief discussed in this article, there is a question of legislative overlap. When is it appropriate to seek a Mareva injunction as opposed to a freezing order under s. 101 of the Courts of Justice Act and Rule 45 of the Rules of Civil Procedure. The answer will depend on the strength of your underlying case and the breadth of assets that you need frozen.

For those who deal with these issues, or who are interested in them, a lunch and learn seminar on contractual obligations of the deceased will be hosted by Wagner Sidlofsky LLP on Nov. 10, 2026, starting at 12 p.m. and presented by Gregory Sidlofsky, Craig Vander Zee and Adin Wagner. For more information and to register please access this link.

Adin Wagner is a lawyer at Wagner Sidlofsky LLP, practising in the estate and commercial litigation groups.

The opinions expressed are those of the author(s) and do not necessarily reflect the views of the author’s firm, its clients, LexisNexis Canada, Law360 Canada or any of its or their respective affiliates. This article is for general information purposes and is not intended to be and should not be taken as legal advice.

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