CPR 19.6(3)(b) “Second Gateway” Does Not Cure Mistaken Defendant Identity Where Liability Is Not Transferred

1. Introduction

These conjoined appeals raised a recurring limitation problem in professional negligence and “successor practice” scenarios: claimants sue a successor firm (here, “BDB”) believing it has taken on the predecessor firm’s liabilities (here, “Pitmans”, later “Adcamp LLP”), only to discover—after limitation has expired—that no transfer of liability occurred.

Parties and background

• Office Properties Appeal: Office Properties PL Limited sued BDB for allegedly negligent advice given by Pitmans in January 2017. Pitmans’ business had been acquired by BDB in December 2018, but with no novation of liabilities. Office Properties later amended to add/substitute Pitmans after limitation had expired.
• Lee Appeal: Mr Lee and Kenilworth Claim Limited retained Pitmans in February 2018 and sued BDB in February 2024 on an assumed-liability basis. After limitation expired, they sought to substitute Pitmans (while also pursuing novation/estoppel/acknowledgment allegations against BDB).

Key issue

Since the “first gateway” in CPR 19.6(3)(a) (mistake as to a party’s name) was conceded to be unavailable (the mistake was as to identity, not name), the core question became whether CPR 19.6(3)(b) / s.35(6)(b) (“second gateway”) allows substitution where: (i) the underlying alleged negligence is the same, but (ii) the legal basis for holding the originally-sued defendant liable (assumption/novation/estoppel/acknowledgment) disappears.

2. Summary of the Judgment

The Court of Appeal allowed both appeals. It held that the second gateway was not satisfied where the claimant’s original claim against BDB depended on additional essential facts establishing BDB’s liability for Pitmans’ negligence (assumption of liabilities etc.), and the proposed substituted claim against Pitmans would omit those essential facts. The claim after substitution would therefore be a different “claim” in substance, and substitution would be an impermissible attempt to “launch a new claim against a new party” after limitation.

3. Analysis

3.1 Precedents Cited (and how they shaped the decision)

(A) The strict boundary of the “first gateway” (name vs identity)

• The Sardinia Sulcis [1991] 1 Lloyd's Rep 201
  Established the distinction between a mistake as to name and a mistake as to identity. Only the former qualifies for the “mistake” gateway. This meant that suing BDB believing it was legally responsible for Pitmans was outside the “mistake as to name” concept.
• Adelson v Associated Newspapers Ltd [2007] EWCA Civ 701; [2008] 1 WLR 585
  Confirmed that The Sardinia Sulcis approach continues under CPR 19.6(3)(a). Bound the Court of Appeal here: a mistake of law/identity cannot be “recast” as a correctable naming error.
• Insight Group Ltd v Kingston Smith [2012] EWHC 3644 (QB); [2014] 1 WLR 1448 ("Insight Group")
  Leggatt J questioned the logic of the name/identity line, but (crucially) his discussion of the second gateway was obiter. The present court accepted it could not revisit Adelson and declined to use the second gateway to mitigate the perceived harshness of the first.

(B) The “second gateway”: “same claim” and the impermissible backdoor

• Nemeti v Sabre Insurance Co Ltd [2013] EWCA Civ 1555 ("Nemeti")
  Central authority on the second gateway. The claimants originally sued an insurer under a statutory indemnity route; after limitation, they sought to substitute the estate of the tortfeasor. The Court of Appeal refused: although the driver’s negligence underlay both, the claims were not the same because the original claim had an “additional and vital element” (the regulation 3 route). The present court applied the same logic: the “additional and vital element” in suing BDB is the pleaded route by which BDB is made liable for Pitmans’ negligence.
• Parkinson Engineering Services plc (in liquidation) v Swan [2009] EWCA Civ 1366; [2010] Bus LR 857 ("Parkinson")
  Allowed substitution of claimant (company → liquidator) where the underlying cause of action remained the company’s and s.212 of the Insolvency Act 1986 provided a procedural route. The present court distinguished it: Parkinson did not involve a substantive change to the identity of the party bearing liability; the “claim” remained vested in the same entity.
• Irwin v Lynch [2010] EWCA Civ 1153 ("Irwin")
  Similarly allowed substitution of claimant where the administrator had no standing but was pursuing the company’s cause of action. Again distinguished: substitution of a claimant with standing (but same vested claim) is not equivalent to substituting a different defendant to impose primary liability where none was transferred.
• Letang v Cooper [1965] 1 QB 232
  Cited for Diplock LJ’s classic definition of a “claim” as a factual situation entitling one person to a remedy against another. The Court of Appeal’s approach ultimately aligned more with the appellants: “the claim” includes the essential facts needed to establish liability against the party sued, not merely the underlying wrong by someone else.
• Various Claimants v G4S [2021] EWHC 524 (Ch); [2021] 4 WLR 46
  Mann J’s comments suggesting “properly” might relate to locus standi-type errors were noted but treated as unpersuasive, particularly because they resembled a “gloss” rejected in Nemeti.

(C) Limitation as a balance mandated by Parliament

• Haward v Fawcetts [2006] UKHL 9; [2006] 1 WLR 682
  Provided the interpretive backdrop: limitation provisions reflect Parliament’s balance between claimant hardship and defendant repose. Courts must apply that balance, not substitute their own. This underpinned the court’s refusal to interpret the second gateway expansively to compensate for the narrowness of the first.

(D) Post-commencement transmission of rights/liabilities: outside s.35

• The Choko Star [1996] 1 WLR 774
  Mance J drew a key distinction: substitution because of a change during proceedings (e.g., merger) does not introduce a “new claim” and raises no limitation issue of the s.35 kind.
• Yorkshire Regional Health Authority v Fairclough Building Ltd [1996] 1 WLR 210
  Approved the Choko Star analysis and emphasised that certain substitutions involve “no question of limitation”. The present court used these authorities to reject an argument that CPR 19.6(3)(c) implies a broad reading of s.35(6)(b).
• Roberts v Gill [2010] UKSC 22; [2011] 1 AC 240
  Reaffirmed that assignments/transmissions after issue generally do not engage s.35. The court relied on this line to explain why “transmission” scenarios do not justify stretching the second gateway to fix pre-issue mistakes about who is liable.
• Re Eurocruit Europe Ltd (In liquidation) [2007] EWHC 1433 (Ch)
  Cited within Parkinson for the proposition that s.212 Insolvency Act 1986 creates no new cause of action—supporting why substitution there preserved the same claim.

3.2 Legal Reasoning

(1) No “merits vs procedure” threshold in the second gateway

The appellants argued the second gateway contains (i) a requirement that the original claim cannot be determined “on its merits” unless substitution occurs and (ii) a requirement that the old and new claim be identical in all material respects. The Court of Appeal rejected limb (i) as a controlling filter. It held that attempts to confine the second gateway to procedural/constitutional defects were effectively a “gloss” akin to that rejected in Nemeti.

The judgment also cautioned against over-reading CPR language (“cannot properly be carried on”) to interpret the statute: the rule cannot control Parliament’s meaning.

(2) The dispositive question: what counts as “the claim” for “same claim” analysis?

The court accepted that the second gateway requires the post-substitution claim to be “the same” in substance as the original. The decisive disagreement was whether “the claim” means:

• Respondents’ view: only the duty/breach/loss facts against Pitmans (treating the BDB-assumption allegations as surplusage); or
• Appellants’ view (accepted): the essential facts needed to impose liability on the defendant actually sued (including the assumption/novation/estoppel/acknowledgment route).

Applying Nemeti, the court held that a claim against BDB for Pitmans’ negligence is not the same as a claim against Pitmans for its own negligence, because the former contains an additional essential element: the basis for fixing BDB with liability for someone else’s wrong. Removing that element is not mere “tidying”: it changes the substance of the claim and would amount to commencing a new action against a new defendant after limitation.

(3) The court refused to let the second gateway circumvent the first gateway

The court acknowledged the “apparent anomaly” that:
• suing the wrong entity because you mistakenly think it committed the negligent act may fall within the first gateway (if treated as name/identity in the permitted sense), whereas
• suing a successor because you mistakenly think it assumed liabilities does not.

But it held that this is a consequence of binding authority on s.35(6)(a)/CPR 19.6(3)(a) (Adelson, The Sardinia Sulcis). The remedy is not to expand s.35(6)(b) artificially; otherwise:

• the second gateway could be invoked even where suing the initial defendant was a tactical choice rather than a mistake;
• it would undercut Parliament’s carefully delimited exceptions to limitation (contrasting with expressly discretionary regimes like s.33); and
• it could spill into other contexts (e.g., vicarious liability) in ways Parliament did not specify.

(4) A procedural note from the Lee Appeal (jurisdiction before discretion)

Zacaroli LJ observed (without criticism) that once the deputy judge concluded the second gateway condition was not presently satisfied, the court had no jurisdiction to make a conditional substitution order. This underscores the structure of s.35/CPR 19.6: discretion arises only after the gateway is crossed.

3.3 Impact

(A) Practical consequences for claimants

• Protective pleading becomes vital: where there is any doubt about successor liability, claimants must consider issuing in time against both predecessor and successor (or obtaining a standstill) rather than relying on post-limitation substitution.
• More front-loaded due diligence: claimants will need earlier investigation of business transfers, novations, partnership/LLP transitions, and insurance/indemnity structures.
• Less room for “course correction”: CPR 17 amendments made before service will not save a claimant if, in substance, they introduce a new defendant after limitation and the first gateway is unavailable.

(B) Defendant-side significance

• Reinforced limitation defences: successor entities will more readily defeat late substitutions where liability transfer is absent or unproven.
• Sharper strike-out pressure: early applications disputing assumed-liability theories can force claimants to confront limitation risk before it becomes irreparable.

(C) Doctrinal significance

• Disapproval of obiter in Insight Group: the Court of Appeal expressly disagreed with Leggatt J’s obiter equivalence between claimant-substitution standing cases and defendant substitution.
• “Same claim” framed by essential liability elements: following Nemeti, the decision entrenches that “the claim” includes the essential legal route fixing the sued party with liability, not merely the underlying wrong.
• Pressure point remains the first gateway: the judgment implicitly signals that any relaxation of the name/identity distinction must come from the Supreme Court (as Singh LJ observed), not through expansion of s.35(6)(b).

4. Complex Concepts Simplified

• Limitation period: a statutory deadline for bringing a claim. After expiry, the defendant usually has a complete defence.
• “New claim” (s.35): includes adding or substituting a party. Such a step after limitation is generally prohibited unless a gateway applies.
• CPR 19.6(3)(a) (“first gateway”): allows substitution where the wrong party was named by mistake for the new party—interpreted narrowly as a mistake of name, not identity.
• CPR 19.6(3)(b) (“second gateway”): allows substitution only if the claim cannot properly be carried on against/by the original party unless the new party is added/substituted. This case holds it does not apply merely because the claimant sued someone mistakenly thought to have assumed another’s liabilities.
• “Same claim”: not every pleaded detail must match, but the essential facts establishing liability against the sued party must. If those essential facts change (e.g., removing “B assumed A’s liabilities”), it becomes a different claim.
• Novation / assumption of liabilities: a legal mechanism by which contractual liabilities are transferred to a new party, typically requiring agreement. Without it, the successor is not liable for the predecessor’s wrongs merely because it acquired the business.
• Estoppel / acknowledgment: doctrines that can, in some circumstances, prevent a party from denying liability or can affect limitation; they are fact-sensitive and distinct from the statutory gateways for adding parties.

5. Conclusion

The Court of Appeal has drawn a clear boundary around CPR 19.6(3)(b)/s.35(6)(b): it is not a mechanism to replace a wrongly-sued defendant with the true wrongdoer after limitation where the original claim depended on a separate, essential “route to liability” against the wrong defendant (such as assumed successor liability). The decision aligns the “same claim” inquiry with Nemeti and distinguishes claimant-standing substitution cases like Parkinson and Irwin.

The broader significance is constitutional as well as practical: limitation rules are Parliament’s balance, and perceived unfairness caused by the narrow scope of the “mistake” gateway cannot be remedied by expanding the second gateway. Any reform of the name/identity distinction is a matter for higher appellate reconsideration or legislation, not interpretive workaround.