Multi-party disputes: map who owes what before anyone sues

A construction project fails, a product is recalled, a critical component turns out defective: real commercial losses rarely involve just two parties. There is a customer, a general contractor, subcontractors, suppliers, an insurer, sometimes a seller under an M&A agreement. The first instinct (sue whoever is closest, or whoever has the deepest pockets) is usually wrong, or at least premature. The better first move costs nothing to file: map who owes what to whom.

One loss, many contracts

In a multi-party situation the loss sits at the end of a chain of bilateral contracts, and each link has its own rules. Your customer's claim against you is governed by one contract; your claim against your subcontractor by another; the subcontractor's against its supplier by a third. Each has its own scope of duties, its own liability cap and exclusions, its own notice and inspection requirements, its own governing law and forum: state courts here, arbitration there. Nothing guarantees these line up. The chain is only as strong as its weakest documented link.

Build the obligation matrix

Before strategy, inventory. For every party in the picture, answer the same questions: What exactly did they owe, by contract, by statute, by warranty? What, arguably, did they breach? What defences will they raise? What cap or exclusion limits their exposure, and does the cap have carve-outs? Were inspection and notice duties complied with, on time and in form? Where would a claim have to be brought, and under which law? Is limitation running, and against whom? Are they solvent, and are they insured? Include your own insurers in the matrix, too: coverage, notification duties and their say in the conduct of the defence are obligations as well, and late notification is an avoidable way to lose cover.

The output is a matrix, not a memo: parties on one axis; obligations, defences and constraints on the other. It is sober work, slower than firing off a demand letter, and considerably faster than discovering the gaps mid-litigation. It changes decisions.

Mind the recourse chain

The matrix usually exposes the central risk: the links do not match. You may be liable to your customer on broad terms while your recourse against the supplier is capped, subject to short complaint windows, or parked in an arbitration clause with a different seat. Where the chain narrows downstream, you keep the difference. Knowing that before anyone sues changes your settlement posture at both ends.

Swiss law adds tools and traps of its own. Where several parties are jointly and severally liable (Art. 143 CO), the creditor may demand full performance from any one of them and leave the internal allocation to a later recourse round (Art. 144 CO). On the procedural side, claims against several defendants can be joined where the same facts and the same legal basis carry them (Art. 71 CPC), with Art. 15 CPC governing where that combined action belongs. A party being sued can also formally involve its recourse partner so the outcome does not have to be fought twice. Whether and how to use these instruments is a genuinely strategic choice.

Sequence deliberately

With the map in hand, choose your battles and their order. Some considerations recur. Do not antagonize the party whose cooperation your recourse depends on before you have secured documents and testimony. Preserve limitation against everyone (interruption is possible, and it buys time) while you negotiate with one. Be careful what you concede in one settlement, because admissions and releases can echo into the other relationships. And weigh whether a party belongs in the dispute at all: suing a partner you will need on the next project is a business decision wearing legal clothes.

Sequencing also has an evidence dimension: proceedings against one party generate documents, testimony and findings that shape the next: sometimes to your advantage, sometimes not.

Decide before positions harden

All of this is cheapest at the start, when the letters are still polite and the files still complete. Sometimes the matrix even shows that a collective commercial fix (everyone contributes, the project gets finished) beats years of litigation in three directions at once. Which claims to bring, against whom, in what order, depends entirely on the facts and the contracts. Mapping them is where we usually start. If a multi-party situation is building around you, it is worth mapping it before anyone sues: including you.