Excluding Declaratory Judgments from the Doctrine of Merger: Nasir v Zavarco Plc ([2025] UKSC 5)

1. Introduction

In Nasir v Zavarco Plc ([2025] UKSC 5), the United Kingdom Supreme Court confronted the vexed question of whether the longstanding English law doctrine of merger—which provides that once a final judgment is obtained, the original cause of action merges into that judgment—extends to purely declaratory judgments. The dispute arose against the backdrop of a high-stakes commercial conflict: namely, whether Tan Sri Nasir (the Appellant) was required to pay €36 million for shares acquired in Zavarco plc (the Respondent).

Declaratory relief had been secured in earlier High Court proceedings, providing clarity that the shares remained unpaid and that Zavarco could forfeit them. Subsequent litigation ensued when Zavarco sought to enforce payment of the debt itself. Nasir argued that the cause of action was barred because it had allegedly merged into the original declaratory judgment. By contrast, Zavarco maintained that declaratory relief alone did not extinguish the underlying right and could not trigger the doctrine of merger.

This case accordingly presented a novel point: whether a declaration is treated as a judgment that operates to extinguish the cause of action in question. As the Supreme Court ultimately held, the doctrine of merger does not apply to declaratory judgments, and the purely declaratory order did not bar Zavarco’s subsequent claim for payment of the shares.

Below is a comprehensive commentary examining the background, judicial findings, and broader implications of this significant ruling.

2. Summary of the Judgment

The Supreme Court unanimously dismissed the appeal brought by Tan Sri Nasir. In essence, the Court held that the doctrine of merger—which is premised on transforming a litigant’s original claim or “cause of action” into the higher nature of a final judgment—applies only to coercive judgments (e.g., those granting a monetary remedy or ordering specific performance). The Court declined to extend merger to purely declaratory judgments, reasoning that a declaration merely confirms legal rights and imposes no new or “higher” obligation.

As a result, Zavarco’s right to claim the unpaid amount for Nasir’s shares was preserved, notwithstanding the High Court’s earlier declaration that the shares were unpaid and could be forfeited. The declaratory relief established the parties’ rights but did not extinguish the underlying debt claim. This distinction reflects a concern for justice, the practical realities of litigation strategy, and adherence to the historical foundation of the merger doctrine.

3. Analysis

A. Precedents Cited

A substantial portion of Lord Hodge’s judgment revisits key historical and contemporary cases that shed light on the doctrine of merger. Notable among these are:

Broome v Wooton (1605): Provided one of the earliest insights into how the original cause of action becomes transformed into a judgment. In the realm of trover, once the claimant obtained damages, the underlying right was considered “changed in nature.”
Higgens’s Case (1605): Demonstrated how a debt secured by a bond merged into a higher, record judgment.
King v Hoare (1844): The Court of Exchequer held that a judgment (even an unsatisfied judgment) against one joint obligor extinguishes the underlying cause of action, preventing a second action against another joint obligor.
Kendall v Hamilton (1879): Confirmed King v Hoare and demonstrated that the merger doctrine can sometimes operate harshly, barring claims even when the debt remains unpaid.
Republic of India v India Steamship Co Ltd (“The Indian Grace”) [1993] AC 410: Illustrated Parliament’s statutory intervention (section 34 of the Civil Jurisdiction and Judgments Act 1982) to extend a bar on fresh proceedings in England when a judgment has been obtained in a foreign or other UK jurisdiction. The House of Lords noted that the principle promotes finality even if it may appear unjust to some litigants.
Virgin Atlantic Airways Ltd v Zodiac Seats UK Ltd [2013] UKSC 46: Lord Sumption provided a helpful taxonomy of res judicata principles, clarifying that merger is a substantive rule that extinguishes a cause of action once coercive judgment is obtained.
Clark v In Focus Asset Management [2014] EWCA Civ 118: Underscored that if a claimant obtains a judgment, it merges the original cause of action into that judgment; the claimant can enforce only the judgment, not sue again on the underlying cause.

Collectively, these precedents form a long lineage illustrating how the doctrine of merger has evolved, sometimes spurring statutory reforms to mitigate potentially harsh outcomes. In each of these key cases, the Court emphasized the necessity of finality, preventing multiple suits over the same subject matter when a higher, coercive remedy has already been granted.

B. Legal Reasoning

Lord Hodge, delivering the leading judgment, retraced the common law roots of the merger doctrine: a longstanding rule developed to ensure that once a litigant obtains a judgment, the lesser (original) right of action merges into the higher, record-based liability. However, the Court stressed that the entire historical basis of merger assumes a coercive remedy—namely, a money judgment or a final order compelling or prohibiting something. Declaratory judgments, by contrast, do not command a defendant to pay, deliver property, or perform an act.

The Supreme Court highlighted several key justifications for resisting the extension of merger to declarations:

Historical Context: Merger emerged when purely declaratory relief was rarely granted. Courts only sporadically entertained declarations as a distinct remedy, so the notion that a “higher” remedy might displace an earlier right did not logically encompass declarations.
Nature of Declaratory Relief: A declaration confirms a legal right but does not alter or fulfill it through enforcement. As a result, there is no transformation or “metamorphosis” of the cause of action into a higher obligation.
Modern Procedural Tools: Courts today have robust procedural powers to control vexatious, repetitive, or abusive litigation. Merger need not be further extended to capture declarations, as doctrines like issue estoppel, cause of action estoppel, and abuse of process (Henderson v Henderson) already control duplicative claims.
Potential Injustice: Rigidly extending merger to declarations could yield outcomes that undermine fairness, barring legitimate recovery merely because a preliminary declaration had been sought. Such a result would be unnecessarily harsh and unconnected to the historical rationale of merger.

On these bases, the Supreme Court confirmed that the earlier declaration that Nasir’s shares remained unpaid and liable for forfeiture did not merge and extinguish Zavarco’s right to later sue for payment of the subscription price. Zavarco’s second claim (for the debt itself) remained intact.

C. Impact

This decision clarifies a formerly unsettled point in English law and will undoubtedly influence future commercial disputes where parties first seek non-coercive, declaratory orders and then pursue tangible relief at a later stage. The key impact of the case includes:

Practice and Litigation Strategy: Litigants may safely secure a declaration without risking the loss of a monetary or other coercive claim, provided no other rule or estoppel doctrine applies. For instance, if a company needs clarity on its contractual rights before enforcing them, a declaration will not extinguish the cause of action for ultimate enforcement.
Merger Doctrine’s Scope: The judgment confines the doctrine of merger to coercive judgments, ending speculation that even a declaratory judgment might transform the parties’ underlying rights (such that subsequent proceedings would be barred).
Certainty in Commercial Disputes: Parties in multi-stage transactions (e.g. share subscriptions, plain or complex financial structures) will benefit from knowing that seeking an initial ruling on a contentious issue does not forever prevent later enforcement of the right that was declared.
Relevance of Other Doctrines: Courts remain vigilant in preventing abuse of process or duplicative litigation through doctrines like cause of action estoppel, issue estoppel, and Henderson v Henderson. Extending merger to declarations was therefore unnecessary to limit potential abuses.

4. Complex Concepts Simplified

Certain concepts at the heart of this judgment can be challenging for non-legal readers. Below are simplified explanations:

Doctrine of Merger: When a court gives someone a “coercive” judgment (like an order to pay money), the original legal complaint merges into this higher legal command. The winning party must then enforce the judgment itself, rather than relying on or suing again on the original cause of action.
Declaratory Judgment: A declaration does not force anyone to pay money or perform a specific act. Instead, it states who is in the right. The Supreme Court decided this type of judgment does not “upgrade” or merge the original cause of action into something new—thus, no single final remedy is created.
Coercive Remedy: A court order costing the defendant money (e.g., damages or debt) or compelling the defendant to act (e.g., an injunction or order for specific performance). It is this sort of command that the courts historically treated as “higher in nature,” giving rise to the merger doctrine.

5. Conclusion

The Supreme Court’s decision in Nasir v Zavarco Plc confirms that a purely declaratory judgment does not bring about the doctrine of merger. The declaratory remedy affirms rights but imposes no new or higher liability that could extinguish the original cause of action. This refined understanding of merger aligns the rule with its historical underpinnings—focusing on judgments that give the successful claimant an enforceable, coercive right.

By maintaining a line between declaratory relief and enforceable or coercive relief, the Court preserves flexibility for litigants to seek clarity on the state of their legal rights without forfeiting subsequent entitlement to damages or other remedies. The judgment also underscores the array of alternative measures to prevent duplicative litigation, ensuring that complex commercial or contractual disputes can proceed in stages if necessary.

Ultimately, Nasir v Zavarco Plc ([2025] UKSC 5) stands as a significant authority on the limits of the merger doctrine. It provides a clear statement that only judgments granting coercive relief extinguish the underlying cause of action, while declarations of right remain outside the doctrine’s scope.