A recent decision of the Full Federal Court has clarified the circumstances in which a party may use documents disclosed in Australian litigation in an offshore proceeding.

Introduction

In Marsh Limited v Greensill Bank AG [2025] FCAFC 186, the Court revisited the scope of the Hearne v Street obligation, more commonly referred to as the “Harman undertaking”.

Overturning the primary judge’s decision, the Full Court held that Marsh did not breach the Hearne v Street obligation when it relied on documents disclosed by the opposing party to support an anti-suit application in English courts. 

The Hearne v Street Obligation: A Quick Refresher 

The Hearne v Street obligation was described by the plurality (Hayne, Heydon and Crennan JJ) in Hearne v Street (2008) 235 CLR 125 at [96]:

Where one party to litigation is compelled, either by reason of a rule of court, or by reason of a specific order of the court, or otherwise, to disclose documents or information, the party obtaining the disclosure cannot, without the leave of the court, use it for any purpose other than that for which it was given unless it is received into evidence…

This principle underpins the discovery process, providing parties with the confidence to disclose confidential documents, safe in the knowledge that such material cannot be misused for collateral or unrelated purposes.

Since Hearne v Street, courts have grappled with the boundaries of this obligation, particularly what constitutes a purpose 'other than that for which it was given.' 

Background

This case arose out of the Greensill Proceedings in the Federal Court of Australia where the applicants are claiming losses of $7 billion against Insurance Australia Limited (IAL) following the collapse of the Greensill group.

During the course of these proceedings, IAL gave discovery of documents to Marsh. Marsh then used these documents in an ex parte anti-suit application in the High Court of Justice of England and Wales, seeking an injunction to restrain Greensill and the other respondents from joining it to the Australian proceedings.

In response, Greensill and the other respondents sought an ex parte anti-anti-suit injunction in the Federal Court of Australia seeking, amongst other things, a declaration that the Marsh entities had breached the Hearne v Street obligation by using the discovered documents in the English proceedings. 

First Instance Decision

At first instance, the Court declared Marsh had used the documents for a collateral purpose, in contravention of the Hearne v Street obligation (see Credit Suisse Virtuoso SICAV-SIF v Insurance Australia Limited (No 2) [2024] FCA 1308).

The primary judge reasoned that the use of the documents for the purpose of an anti-suit application which sought to prevent the Court from exercising its jurisdiction was the “antithesis of the purpose of the conduct of the Greensill Proceedings”.  

The Full Court's Findings

On appeal, the Full Federal Court took a different view. Allowing the appeal, the Court found Marsh had not contravened the Hearne v Street obligation. The Full Court clarified the test at [57]:

In our view, a formulation of the relevant test that is directed at a purpose that is “connected with” or “related to the determination of” a “dispute” between parties, rather than at a purpose that is confined to the use of the disclosed documents or information in the specific proceeding in which it was disclosed, produces a test that is better placed to capture the “purpose … for which [the discovery] was given”, as stipulated in Hearne v Street at [96].

As the anti-suit application involved asking a Court to prevent a party from causing a Court to exercise jurisdiction in relation to the claim, this was a purpose directed at the "conduct of" a proceeding in a Court. The conduct of a proceeding necessarily encompasses both claims that are permitted to be pursued and those that are not. 

The Full Court was not required to decide whether the Hearne v Street obligation yields to the English law obligation of full and frank disclosure on an ex parte application, which was a key aspect of the decision at first instance.

Key Takeaways

The Court's decision signals a shift away from a narrower, technical reading of the Hearne v Street obligation in the context of an anti-suit injunction. Rather than confining the use of discovered documents strictly to the specific proceeding in which they were disclosed, the Court has embraced a more purposive approach.

In appropriate circumstances, documents discovered in Australian litigation may be used in foreign proceedings, if that foreign proceeding is sufficiently connected to the dispute at the heart of the Australian litigation.

This is particularly relevant for parties involved in cross-border disputes, where the same factual matrix may give rise to parallel or related proceedings in multiple jurisdictions.