Reinsurance disputes are almost never decided by national courts. For more than a century, the London market — the world's largest concentration of reinsurance capacity — has preferred to resolve its differences privately, before arbitrators drawn from the market itself. The result is a body of practice that is largely invisible to outsiders: awards are confidential, precedents circulate informally, and the governing framework, today embodied in the ARIAS (UK) Arbitration Rules, is known mainly to practitioners.
This article explains how reinsurance arbitration works in London, with particular attention to a question that often puzzles cedants and counsel from civil-law jurisdictions: what happens when the counterparty is not a company at all, but a Lloyd's syndicate? It closes with a Moroccan perspective — how a Moroccan cedant or an African reinsurer engages with this system, and how a London award is enforced in Morocco.
I. The London market and the preference for arbitration
Reinsurance is a business conducted between professionals who expect to deal with each other again. That single fact explains most of what follows. A cedant and a reinsurer in dispute over one treaty year are usually still partners on the next; neither wants a public judgment, a hostile cross-examination of its underwriters, or a precedent that binds the rest of its book. Arbitration offers what courts cannot: confidentiality, decision-makers who understand how risks are placed and claims are adjusted, and the flexibility to resolve a dispute by reference to market custom rather than strict legal technique.
The practice is old. Reinsurance treaties placed in London have carried arbitration clauses since the nineteenth century, and the standard market wordings — including the Joint Excess Loss Committee (JELC) clauses used in excess-of-loss treaties — all provide for arbitration in London. The seat matters: an arbitration seated in London is governed by the Arbitration Act 1996 (as amended by the Arbitration Act 2025), which gives the parties broad procedural autonomy, strictly limits court intervention, and produces an award enforceable in some 170 States under the New York Convention of 1958.
Two consequences follow for anyone advising on a London-market treaty. First, the dispute-resolution landscape is almost entirely private: there is no database of reinsurance awards, and the few reported court decisions arise only from applications ancillary to arbitration — appointment or removal of arbitrators, challenges to awards, anti-suit injunctions. Second, expertise in this field is held by a relatively small community of market arbitrators, specialist solicitors and barristers, and the institutional home of that community is ARIAS (UK).
II. The ARIAS (UK) framework
ARIAS (UK) — the AIDA Reinsurance and Insurance Arbitration Society — is the specialist body of the London market for insurance and reinsurance arbitration. It is not an administering institution in the sense of the ICC or the LCIA: ARIAS arbitrations are, in substance, ad hoc proceedings conducted under the ARIAS (UK) Arbitration Rules (3rd edition, 2014), with ARIAS intervening mainly as appointing authority when the parties' mechanism fails. ARIAS also publishes model arbitration clauses, a Fast Track procedure for smaller disputes, and maintains a panel of arbitrators drawn from the market. Sister bodies exist in the United States (ARIAS·US) and continental Europe (ARIAS Europe).
Constitution of the tribunal. The parties are free to agree the number and qualifications of the arbitrators (Rule 6.1). In default, the tribunal consists of three arbitrators: one appointed by each party, the third by the two party-appointed arbitrators, acting as chairman and not as an umpire (Rule 6.2). The signature requirement of the market is the qualification clause: arbitrators must be persons — including those who have retired — with not less than ten years' experience of insurance or reinsurance within the industry, or as lawyers or other professional advisers serving the industry. The scope of that requirement has itself been arbitrated and litigated: in Allianz Insurance plc v Tonicstar Ltd [2018] EWCA Civ 434, the Court of Appeal held that a barrister with over ten years' practice in insurance and reinsurance law satisfied a “ten years' experience of insurance or reinsurance” clause, overturning seventeen years of contrary authority. The JELC clauses were amended with effect from 1 January 2018 to state the position expressly.
Procedure. The procedure is deliberately lean. There is no institutional case management; the tribunal fixes the timetable, written submissions are exchanged with documents, disclosure is narrower than in English litigation, and hearings are short by court standards, with heavy reliance on underwriting and claims witnesses and on market expert evidence. Confidentiality is implied as a matter of English law and reinforced by the Rules.
The honourable engagement clause. The most distinctive feature of reinsurance arbitration is the clause — contemplated by Rule 17.1.3 of the ARIAS Rules and standard in market wordings — providing that the arbitrators shall interpret the contract as an honourable engagement rather than merely as a legal obligation, and shall not be bound by strict rules of law or evidence. Its purpose is to let the tribunal give effect to the commercial intent of the treaty and to market custom and practice, rather than to defeat that intent on a point of drafting. English law gives effect to such clauses under section 46(1)(b) of the Arbitration Act 1996, which allows the tribunal to decide “in accordance with such other considerations as are agreed by the parties”. For a civil lawyer, the closest analogue is amiable composition — but confined by the treaty's own commercial purpose, not a licence to decide in pure equity.
III. Arbitrating with a Lloyd's syndicate
A substantial share of the reinsurance protecting African and Middle Eastern cedants is written at Lloyd's. Yet “Lloyd's” is not an insurance company, and a syndicate is not a legal person — a point with real procedural consequences that counsel outside London frequently miss.
What a syndicate is. Lloyd's is a market constituted under the Lloyd's Acts 1871–1982, in which capital providers — the members, today mostly corporate — accept risk through syndicates. A syndicate is simply the group of members underwriting through a given channel for a given year of account; it has no corporate personality. The business is run by a managing agent, a company authorised by Lloyd's, whose active underwriter subscribes risks on the members' behalf. Each year of account is a separate venture, traditionally closed after three years by reinsurance to close (RITC), by which a later year — or increasingly a legacy carrier — assumes the liabilities of the earlier one.
Who is the party to the arbitration? The reinsurance contract is made with the members of the syndicate for the relevant year of account, severally and not jointly, each for his own share. In practice, proceedings are brought against a representative underwriter — the lead or the active underwriter “for and on behalf of” the subscribing members — identified from the slip or the market reform contract. Three practical rules follow. First, identify the correct year of account: a 2019 loss engages the 2019 members, who may differ from those of 2024. Second, where RITC has occurred, the economic respondent may be a legacy reinsurer, although the contractual counterparties remain the original members. Third, where several syndicates subscribe the same treaty, each subscription is a separate contract: the claimant may face parallel arbitrations unless consolidation is agreed, which is why market clauses and the ARIAS framework encourage common tribunals for followers.
Service and representation. Notices of arbitration are served on the managing agent, and the defence of claims is in practice conducted by the managing agent's claims team with London solicitors instructing specialist counsel. The capital behind the syndicate never appears.
Enforcement. An award against the subscribing members is enforced like any other English award. The practical comfort for a foreign claimant lies in Lloyd's chain of security: members' funds at Lloyd's and, ultimately, the Central Fund stand behind valid claims, so that enforcement against a solvent syndicate is rarely contested once the award is final. Where enforcement abroad is needed, the award travels under the New York Convention in the name of the members or their representative underwriter — and the drafting of the title of the proceedings at the outset determines how smoothly that recognition goes.
IV. The Moroccan perspective
Moroccan cedants, and African reinsurers more generally, meet London arbitration from two directions: as claimants pursuing reinsurance recoveries, and as respondents when a reinsurer disputes aggregation, late notice or the application of a claims-cooperation clause. Three points deserve emphasis.
The treaty must be read as the market reads it. Reinsurance treaties placed in London are construed by tribunals steeped in market practice — follow-the-settlements and follow-the-fortunes clauses, the presumption of back-to-back cover in proportional treaties, aggregation by “event” or “originating cause”, honourable engagement. A cedant that approaches the dispute through the lens of its domestic civil code alone, without an understanding of how these concepts are actually applied by London tribunals, starts at a structural disadvantage. The legal nature of the reinsurance treaty itself — a contract sui generis, distinct from the underlying insurance it protects — remains the indispensable starting point of any coverage analysis.
Morocco is an arbitration-friendly seat of enforcement. Morocco has been a party to the New York Convention since 1959, and Law No. 95-17 on arbitration and conventional mediation (2022) now provides a modern, self-standing framework. A London award is recognised in Morocco through exequatur before the president of the competent court; review is limited to the grounds familiar from Article V of the Convention — validity of the agreement, due process, scope of the mandate, and public policy — with no review of the merits. The confidentiality of the underlying arbitration survives enforcement in practice, since only the award and the agreement are produced.
The direction of travel is African. Casablanca is positioning itself as a regional financial and legal hub, and African cessions into the London and continental markets are growing. Disputes will follow the premium. The underlying covers are as varied as the market itself — marine and transport, property and natural-catastrophe programmes, engineering and energy, financial lines — and each raises its own questions of local law. Civil liability is only one segment of the reinsured book, but it offers a telling example: the insured's responsibility under Articles 77, 85 and 88 of the Moroccan Dahir des obligations et des contrats is often presumed rather than fault-based, in ways that surprise foreign markets. For reinsurers writing Moroccan and African risks, the combination that matters is that line-by-line local-law analysis of the underlying risk, paired with a genuine command of London arbitration practice on the reinsurance layer. Few practitioners stand on both sides of that bridge.
Conclusion
Reinsurance arbitration in London is a system built by the market, for the market: specialist arbitrators, lean procedure, honourable engagement, and — where Lloyd's capacity is involved — a counterparty whose very identity requires careful handling. For cedants and reinsurers operating between Africa and London, the decisive skill is bilingualism in the broad sense: fluency in the custom of the London market and in the law that governs the underlying risk. Disputes are won or lost at the point where the two meet.
By Dr Abdelatif Laamrani, Founding & Managing Partner, Laamrani Law Firm — Casablanca · Paris · Montréal. Author of « La nature juridique du traité de réassurance », The MENA Business Law Review (LexisNexis), 2018/3, and of Droit bancaire marocain (LexisNexis, 2023).