Battle of the Forms in CISG Contracts with Turkish Parties: Whose Terms Apply?

When a foreign company and a Turkish supplier each send their own standard terms and conditions, the CISG generally resolves the conflict through its rules on offer, counter-offer and material alteration, and performance without objection can still leave open which set of terms actually governs disputed issues such as liability limits or warranties.

A battle of the forms occurs when purchase orders, order acknowledgements and invoices each attach different standard terms, none of which the other side has expressly agreed to. This is extremely common in cross-border trade with Turkish manufacturers and trading companies, where each side simply attaches its own boilerplate to routine paperwork.

The CISG treats an acceptance containing additions or modifications as a rejection and counter-offer if the additions materially alter the terms of the offer. The CISG itself lists categories treated as material, including price, payment, quality, quantity, place and time of delivery, liability limits and dispute resolution. Where the CISG's provisions leave a gap, Turkish domestic contract law under the Turkish Code of Obligations No. 6098 may supply supplementary rules, though Turkish courts and tribunals generally try to resolve battle-of-the-forms disputes within the CISG's own framework first.

Practice under the CISG in Turkish commercial courts and in international arbitrations seated in or involving Türkiye tends to follow the "last shot" analysis in a modified form: if the parties proceed to perform after exchanging conflicting forms without either side objecting, courts commonly look at which terms were last communicated and not objected to, while also considering whether the conflicting clauses simply cancel each other out, known as a "knock-out" approach, leaving the CISG's own default rules to fill the gap.

There is genuine debate, both internationally and among Turkish practitioners, between the "last shot" rule, which favours whichever party sent the final set of terms before performance began, and the "knock-out" rule, which disregards conflicting standard terms and applies the CISG's default provisions instead. Which approach a Turkish court or tribunal favours can materially change the outcome on issues such as limitation of liability or dispute resolution clauses.

A battle-of-the-forms analysis becomes necessary whenever each party's documents include standard terms that conflict on a material point and the parties proceeded to perform the transaction anyway. The party invoking a particular clause, for example a liability cap or an arbitration clause, needs to show that clause was actually incorporated into the contract that was ultimately concluded.

Objections to additional or conflicting terms should be raised promptly; a party who receives a confirmation with materially different terms and proceeds without objection risks being treated as having accepted a counter-offer on those terms. There is no fixed statutory deadline for such an objection under the CISG, but delay weakens the argument that the terms were never agreed.

Disputes over whose standard terms apply are decided by the court or arbitral tribunal with jurisdiction, applying the CISG as the substantive law governing the sale. Where the parties' conflicting forms each nominate a different forum or arbitral seat, that conflict itself often becomes a preliminary jurisdictional dispute requiring separate resolution.

The full paper trail matters: the original purchase order, the supplier's order confirmation or acknowledgement, any invoices, and evidence of which version of standard terms was attached to each document and when it was sent and received. Evidence of prior consistent dealings between the same parties can also affect how a battle of the forms is resolved.

A frequent mistake is assuming that whichever party's terms appear on the invoice automatically govern the contract; invoices sent after performance has begun typically cannot retroactively impose new material terms. Companies also mistakenly believe that referencing "our standard terms apply" without attaching or clearly incorporating them is sufficient to bind the other side.

If both sides sent conflicting terms and the goods were delivered, is there still a contract? Yes. Performance despite conflicting standard terms typically confirms that a contract exists; the open question is which specific terms govern.

Does the CISG follow a strict last-shot rule? Not necessarily. Turkish practice, consistent with broader CISG jurisprudence, often applies a knock-out approach to conflicting boilerplate, filling gaps with the CISG's own default rules.

Can a liability limitation clause survive a battle of the forms? Only if it was actually incorporated into the contract that was ultimately concluded, which depends on whether it was communicated and not materially altered by the other side's response.

Should companies still negotiate terms individually with Turkish counterparties? Yes, particularly for high-value transactions, negotiating and expressly confirming key terms in a single agreed document avoids uncertainty from a battle of the forms.

We frequently reconstruct the exact sequence of documents exchanged with a Turkish counterparty to determine which liability, warranty or dispute-resolution clause actually survived the exchange of standard terms, since this analysis often decides the outcome of a later dispute before its merits are even reached.