The global insurance broker Marsh has just had a major setback in its defence of a major lawsuit over its role as insurance broker to failed Greensill Bank AG.
In a decisive ruling from the Federal Court of Australia, Greensill has succeeded in stopping the insurance broker from pursuing legal action in London that could have blocked its Australian claims. The court granted what’s known as an "anti-anti-suit injunction", effectively barring Marsh Ltd (UK) and Marsh Pty Ltd (Australia) from trying to derail Australian proceedings through the English courts.
Justice Thawley’s decision marks another twist in the long-running legal fallout from the collapse of Greensill Capital in 2021, as insurers, brokers and investors continue to battle across multiple jurisdictions over who should bear responsibility for billions in losses.
The ruling prevents Marsh from taking further steps in a London lawsuit where it is trying to enforce exclusive jurisdiction clauses, claiming Greensill is contractually bound to resolve disputes in England. Those clauses appear in letters of engagement between Marsh and Greensill Capital’s UK affiliate, which Marsh says also apply to Greensill Bank in Germany.
But the Australian court found Marsh’s efforts were interfering with live proceedings properly brought in Australia—where the scale and complexity of claims are much broader, including allegations of misleading conduct, negligence and regulatory breaches.
Greensill has now joined Marsh to seven of the eleven so-called "Greensill Proceedings", which also target Insurance Australia Group (IAG), Bond & Credit Co, and Tokio Marine. The claims seek over A$7 billion in damages and compensation related to insurance policies that allegedly failed to respond when Greensill’s business collapsed.
Back in July 2024, Marsh had moved quickly to seek an anti-suit injunction in the High Court in London, aiming to stop Greensill from joining it to the Australian actions. That effort was largely unsuccessful, with the English court only granting narrow relief relating to one specific engagement letter. It found there wasn’t a strong enough contractual basis to support Marsh’s broader claims that Greensill Bank was bound by the English forum clause.
Following this, Marsh amended its case in London to seek a mandatory injunction—this time asking the court to compel Greensill to halt its Australian claims. It also sought damages for alleged breach of contract. In response, Greensill turned to the Federal Court to shut down that move, arguing the London case had become an attempt to undercut Australia’s jurisdiction over its own proceedings.
Justice Thawley agreed. In his judgment, he said the English case was being used to try to stop Greensill from pursuing statutory claims under Australian law, including those for misleading conduct—claims that couldn’t be brought in England. He described Marsh’s efforts as having a "tendency to interfere" with the administration of justice in Australia.
Marsh had argued that the court should refuse relief out of respect for the English legal process. But the judge dismissed that, noting that while principles of international comity require caution, they don’t require Australia to simply step aside. "Comity requires proper respect," he said, "not reflex genuflection."
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The court also found that even if Marsh did have a case under English contract law, it didn’t justify trying to shut down ongoing proceedings in another jurisdiction—particularly when Marsh could raise its arguments in the Australian court.
This isn’t the only legal front facing Marsh. In May this year, the firm reached a confidential settlement with White Oak, a US private debt investor that had sued Marsh in London for $143 million, alleging fraudulent misrepresentations about insurance arranged for Greensill-backed investments. That case exposed embarrassing internal emails where Marsh executives described the situation as “a frightening absence of corporate governance” and “fraud”.
The broader Australian litigation, meanwhile, is expected to run for years. A five-month trial has been set to begin in August 2026, covering multiple overlapping insurance and broker-related claims from Credit Suisse, White Oak and others. Marsh has been accused in several of those cases of misrepresenting the existence or validity of insurance coverage, and of failing to properly disclose key developments as Greensill’s business unravelled.
The Federal Court’s ruling is a clear signal that Australian judges won’t hesitate to assert their authority when foreign proceedings threaten to derail complex local litigation. For Marsh, it means it must now continue defending itself in Australia—and cannot rely on the English courts to put a stop to it.
The ruling also reinforces the risk brokers face when operating across multiple legal systems, particularly in high-value insurance arrangements tied to fast-moving financial products. Jurisdiction clauses, while useful, are not bulletproof—especially when statutory consumer and investor protections are involved.
Case details
Greensill Bank AG v Insurance Australia Ltd (Anti-Anti-Suit Injunction Application) [2025] FCA 1241
Federal Court of Australia, NSW Registry
Judgment by: Justice Thawley
Hearing: 1–2 September 2025
Decision: 10 October 2025
Greensill represented by: Quinn Emanuel Urquhart & Sullivan
Marsh represented by: Johnson Winter Slattery
The Australian proceedings are due to be heard in full from August 2026. Marsh, now locked in, faces potentially extensive liability—and scrutiny—as the Greensill saga continues to play out on the global litigation stage.
