Buyer Changes Specifications Mid-Production: Who Bears a Chinese Supplier’s Delivery Delay?

A buyer’s request to change a product does not automatically give a Chinese supplier an unlimited extension of time. Equally, a buyer cannot assume that it can insist on new specifications while holding the supplier responsible for every consequence of that change. The dispute usually requires two separate findings: what the parties agreed to change, and what actually caused the missed delivery.

This guide addresses commercial goods orders involving a mainland Chinese supplier and a foreign buyer. It focuses on revisions to drawings, materials or packaging during production. Contract classification and governing law must be checked before applying these rules to a predominantly service, construction or processing arrangement.

1. Establish the original obligation and the precise revision

Keep the accepted purchase order, framework terms, original drawing revision, approved sample and original delivery obligation together. A promise to ship by a particular date is different from a promise that the goods will arrive by that date. Record any condition linking production time to receipt of a deposit, approval of a sample or provision of specified information.

Then identify the proposed change: which dimensions, material, test standard, quantity or packaging were altered; which batch was affected; who requested it; and which version reached the supplier. Asking whether a different component is available is not necessarily an instruction to replace the agreed component. A revised file attached to a message also needs to be read with the message and the supplier’s response.

Separate technical approval from agreement on price, delivery and liability. A purchasing employee’s authority to approve a drawing should be checked rather than assumed to include authority to waive accrued delay claims. Preserve the complete correspondence and attachments, including messages that qualify or reject a proposal.

2. Determine whether the contract was actually modified

If the United Nations Convention on Contracts for the International Sale of Goods (CISG) governs, Article 29 permits modification by agreement. Article 8 requires statements and conduct to be interpreted in context, including negotiations, established practices and later conduct. A short reply acknowledging receipt should not be treated, without that context, as acceptance of every proposed commercial change.

Article 29(2) addresses written contracts requiring modifications to be in writing, including the limited situation where a party’s conduct and the other’s reliance prevent reliance on that requirement. Applicable form rules and declarations under Articles 12 and 96 must also be checked. Neither “there is no signed addendum” nor “the engineer replied OK” alone resolves the issue.

Where Chinese domestic law governs the relevant issue, Civil Code Article 543 permits modification by mutual agreement. Article 544 provides a presumption against modification where its content is unclear. Article 469 recognises qualifying retrievable electronic communications as written form; that does not prove assent, authenticity or authority in a particular exchange.

CISG applicability depends on its scope, the parties’ relevant places of business, declarations and any effective exclusion. China’s declaration concerning Article 1(1)(b) remains relevant to mainland transactions. Do not simply combine domestic modification rules with Convention rules as if they were interchangeable.

3. Distinguish a revised deadline from buyer-caused delay

First ask whether the parties agreed to a new delivery date, an extension formula or a defined pause. Check the batches covered and whether the agreement deals with delay that had already occurred. Agreement to a revised delivery schedule does not by itself settle every earlier loss; conversely, a unilateral reservation of rights cannot undo an extension that the parties actually agreed.

A separate question arises where the deadline was not clearly changed but the buyer’s conduct affected performance. CISG Article 80 prevents a party from relying on the other’s failure to the extent that its own act or omission caused that failure. This is a causation inquiry, not a general immunity whenever a buyer has requested a revision.

Request dated records showing when the factory received usable information, which production step depended on it, what work had already been completed, what rework became necessary and what happened after approval. Distinguish that effect from earlier capacity shortages, the supplier’s own errors or work on an unaffected batch. Where domestic law applies, Article 592 addresses each party’s corresponding responsibility for their respective breaches and possible reduction of damages where the injured party contributed through fault to its loss.

A request for seven extra days and a delivery that is twenty days late do not establish either seven or twenty legally excused days. Overlapping causes, the original readiness of production and the effect on the actual delivery milestone require evidence. There is no automatic fifty-fifty allocation.

4. Build an order-specific evidence table

Issue	Records to preserve and compare
Original obligation	Accepted order, controlling specifications, original delivery milestone and any agreed approval conditions.
Requested change	Dated revision files, marked differences, affected quantities and batches, sender identity and complete messages.
Agreement and scope	Supplier’s full reply, authorised confirmation, revised price or date, change-control requirements and treatment of existing claims.
Actual consequences	Production and rework records, procurement dates, inspection results, shipping records, loss documents and mitigation steps.

Keep disputed assertions in a separate column. A supplier’s retrospective spreadsheet is a claim to test against records; a buyer’s internal target date is not necessarily the contractual deadline. Preserve original electronic files and their version history, rather than relying only on cropped screenshots of favourable messages.

5. Resolve the remaining order without losing track of existing claims

A practical change confirmation should identify the controlling revision, affected batch, additional price or cost allocation, the revised delivery milestone, approval dependencies and which original terms continue. State expressly whether earlier delay claims are reserved, released or left disputed. Avoid an unexplained “all matters settled” sentence in a technical confirmation.

For a live dispute, ask the supplier to identify the specific buyer instruction and the supported period of impact. Respond with the buyer’s version of the chronology and identify the remedy sought. Do not treat a unilateral debit note as an admitted debt, or assume that a disagreement over changes alone permits withholding the entire price or cancelling the order.

Damages require their own analysis, including causation, foreseeability and reasonable mitigation under CISG Articles 74 and 77, or the applicable domestic rules including Civil Code Articles 584 and 591. Avoid double-counting an agreed price adjustment and the same loss. If cancellation or a refund is sought, review the separate termination conditions and notice requirements before acting.

6. Prepare a focused China legal review

For an initial review, provide the parties’ legal names for conflict checking, their relevant countries, the order, successive specifications, complete change correspondence, agreed and actual dates, payments, claimed losses and any urgent deadline. Explain whether the objective is a workable delivery plan, rejection of an unsupported surcharge, a negotiated settlement or assessment of proceedings in China.

After conflict and matter checks, work can be scoped around the controlling contract, authority and modification evidence, delay allocation, notices and the agreed dispute route. Service scope, fees and engagement arrangements should be confirmed before representation starts. Sending an enquiry does not itself establish an engagement or guarantee recovery.

Related guides: late-delivery liquidated damages; supplier and subcontractor responsibility; cancelling a custom order before shipment.

China trade dispute legal services · Contact and initial information · panjianxing46@gmail.com

Official sources reviewed on 21 October 2026: CISG text in the official legislative schedule, Articles 1, 6, 8, 12, 29, 74, 77, 80 and 96; United Nations depositary status and declarations (Convention entry into force: 1 January 1988); Civil Code of the People’s Republic of China, Articles 469, 543–544, 584, 591–592 and 601, effective 1 January 2021 under Presidential Order No. 45. The Canadian legislative website is cited for the Convention text, not as a conclusion that Canadian law governs the transaction.

General information, not a legal opinion on a specific order. The day-count illustration is hypothetical and is not a case result. Author: Jianxing Pan, Partner, Beijing Chang’an Law Firm. Cover: AI-generated conceptual illustration, not an actual client, case or shipment photograph.