Most buyers believe that collecting documents is due diligence. I don't. A folder full of PDFs proves very little on its own — some of the 8 documents below any trading company can produce in five minutes. What matters is which documents actually tie back to a real factory, and which ones only mean something if someone is physically standing in that factory to confirm they're real.
The short answer: request the business license, export license or agent agreement, a recent third-party audit, product test reports, the national credit record, dated factory photos, a signed sealed-sample sheet and a formal sales contract. The license scope, certificates and sealed sample are the three that most often fail when someone checks them against the actual factory.
So next to each document I've marked the split: what you can check yourself, and where you genuinely need boots on the ground. The “typical case” scenarios under each one are illustrative examples of how these gaps show up, not accounts of specific clients, and the amounts in them are examples.
Why Do Documents Matter, and Why Are They Not Enough?
Three reasons to ask for all eight:
- They remove excuses. After money has moved, "the factory says" and "it got lost in translation" are hard to argue with. In writing, they are not.
- Some tie back to a real factory. The license scope, the certificates and the sealed sample are the ones that most often fail when someone checks them against the actual factory.
- Paper can be produced by anyone. Some of the documents a trading company can produce in five minutes, so they only mean something when checked on site.
1. Business License (营业执照): Is It Really a Manufacturer?
Every legitimate Chinese manufacturer has one. The registered business scope should say "manufacturing" — not "trading" or "consulting" — for the category you're buying.
This is the document I'd read first, because the scope line settles more than people expect. When our team once checked four "Verified Supplier" storefronts claiming to be manufacturers, all four turned out to be registered as trading or import-export entities, with no manufacturing scope for the product at all. The same gap shows up in auto parts.
A typical case: a buyer sourcing aftermarket wheel rims and hub caps for the BYD Seal and Han finds a storefront showing a 40,000-square-meter facility and video of a CNC forging line running. He sends a 30% deposit on 800 wheel sets.
What the license shows: when he finally gets a copy, the registered scope is "wholesale of auto parts and accessories" — no manufacturing designation anywhere.
The outcome: what arrives eleven weeks later comes from a subcontractor in another province: several sets with bent spokes out of the box, and roughly one in six with a center bore that doesn't match the hub it was sold for. The seller blames "the factory" and stops answering.
The takeaway: read the scope line before the deposit, not after the delivery.
Ask for a photo of the license and read the registered business scope line yourself.
Our team cross-checks the license number against China's National Enterprise Credit system and confirms the registered address matches the actual factory.
2. Export License or Agent Agreement: Who Actually Ships Your Goods?
Not every real factory holds its own export license — some route shipments through a licensed agent, which is normal. What matters is knowing which one you're paying.
Ask directly whether they export themselves or through an agent, and get the agent's name if so.
We confirm the export paperwork used on your actual shipment matches the entity you're paying — not a third party inserted at the last step.
3. Third-Party Factory Audit Report: Is the Factory on the Video Really Theirs?
A factory proud of its operation usually has a recent audit — SGS, Bureau Veritas, or independent — and will share the report number without hesitation.
Suspension parts expose this gap in a different way.
A typical case: a buyer ordering 1,500 sets of control arm bushings sits through two video calls looking at what he's told is the factory floor — production lines in the background, workers at benches.
What an audit would have shown: the address on his shipping documents traces to a small logistics office, and the "production line" footage was recorded at a different company's plant.
The outcome: the bushings arrive molded from a harder durometer rubber than specified. They don't fail immediately — they fail differently: transmitting more vibration into the cabin and cracking sooner under load than the compound he ordered.
The takeaway: a video call shows you a floor; an audit tells you whose floor it is.
Ask if an audit exists from the last 12 months and request the report number.
If no recent audit exists, our team runs one — production line count, equipment, and workforce headcount confirmed in person, not from a brochure.
4. Product Test Reports and Certifications: Do They Cover Your Exact Model?
CE, RoHS, FCC, DOT — whatever your destination market requires — should exist for the exact product model, not a similar one from the same catalog.
This matters most on parts with a legal compliance requirement, and LED headlight assemblies are the clearest example.
A typical case: a buyer ordering 2,400 headlight assemblies for the US aftermarket receives a certificate stamped DOT-compliant, with a certification number printed right on the invoice.
What the check reveals: the number doesn't correspond to anything — because DOT certification for lighting isn't issued by a lab or agency at all; it's a manufacturer's self-declaration, so the stamp alone proves nothing about what's inside the housing. The units run driver chips pushed past rated output to advertise higher lumens.
The outcome: within four months of installation, failure reports describe melted housings and burned-out resistors — heat the design was never built to dissipate.
The takeaway: a stamp is not a test report. Counterfeit safety certification labels on parts like these can bring serious legal exposure for the importer, not just returns.
Ask which lab issued the certificate and for the certificate number.
We confirm the certificate number is real and matches the exact model you're ordering.
$49
Written report in 48 hours: company registration, manufacturer vs. trader, and payment-account match.
Request the $49 check5. National Enterprise Credit Record: Are There Red Flags on File?
China's public credit registry (gsxt.gov.cn) shows registered capital, business scope, and any flagged irregularities — for anyone who can read it. See what registered and paid-in capital mean.
You can run a basic lookup yourself using the company's Chinese legal name.
Our bilingual team interprets what the record actually shows in context — irregularities that aren't obvious if you don't read Chinese regulatory filings regularly.
6. Dated, Unedited Factory Photos: Does the Factory Exist Right Now?
Stock catalog photos tell you nothing. A photo with today's date visible tells you the factory exists right now, as described.
Ask for a photo with today's date written on paper and held up in frame.
We take our own timestamped original photos and video during the visit, so you have evidence you didn't have to ask for.
7. Sealed Sample Confirmation Sheet: Can You Prove the Bulk Doesn't Match?
Without a written record of exactly what was approved, "the bulk order doesn't match the sample" becomes impossible to prove either way.
Brake components are where this gap costs the most.
A typical case: a buyer approves, in writing, a sample set of brake pads built with an ECE R90-rated friction compound, the rating required for EU type approval.
What changed: the bulk order of 6,000 sets that ships six weeks later uses a cheaper, unrated compound blended in-house to hit the target price — same dimensions, same box, same part number, different chemistry. Nothing in the paperwork catches it, because the certificate on file is still the one issued for the sample batch.
The outcome: the swap surfaces only when a customer in Germany fails a roadworthiness inspection, and the buyer has to recall stock already sitting in distributors' warehouses.
The takeaway: only a check of bulk production against the physical sealed sample catches a compound swap.
Insist on a signed sheet describing material, color, and dimensions of the approved sample.
We compare the bulk production line against the physical sealed sample — not a photo of it.
8. Formal Sales Contract or Proforma Invoice: Is Every Term in Writing?
Specifications, quantity, quality standard, packaging, and delivery date — in writing, before any payment leaves your account. Add the exact product description and part number too: your customs broker needs them to confirm the tariff fraction (HS codes and Mexican tariff fractions).
Get every term above written into the order confirmation, not just agreed to in chat.
We go through the Chinese contract with you clause by clause, flag the key terms (payment, delivery date, quality standard, liability for breach) and translate the main points. We are not lawyers and do not give legal advice.
If you want someone independent to check the supplier or the goods, our guide to choosing a factory verification provider compares the options, and our inspection standards show how a pre-shipment check is done.
If you would rather have someone check this in person before you pay, see how our factory verification service works.
Summary: Ask for All Eight, Then Check Them Against the Factory
None of these 8 documents guarantees a perfect order. What they do is remove the excuses — "the factory says," "we'll check and get back to you," "that got lost in translation" — that show up after money has already moved. Over time I've come to watch the process as closely as the papers: a supplier with nothing to hide produces all 8 without friction. One that stalls on two or more is telling you something, whether or not they say it out loud.
In short, collect the documents, but treat them as the start of the check, not the end. If the paperwork is never compared with the real factory, the realistic risk is a first batch that does not match the certificate on file or the sealed sample, which ties up your cash and delays the next order. A $49 remote check looks at the business registration for you, and our team can compare the rest with the factory floor in Guangzhou.
I provide supplier verification services, so you should treat my recommendation accordingly.
Supplier Verification
Factory Visits
Due Diligence
Verification