We are a factory, and this is the list we hand to our own buyers. It is written to be used on us as much as on anyone else — two of the seven checks are the ones a trading house cannot pass, and the rest cost you nothing but an afternoon.
A factory can show you the machines that make your part and the tooling that shapes it. A trading company can show you a showroom, a certificate wall and a very good website. Both will tell you they are the manufacturer.
The fastest tell is not the paperwork — it is whether the company can do an unscripted walk-through at short notice, and whether its registered business scope includes manufacturing. Everything else on this list is confirmation.
Every registered company in China has an 18-character unified social credit code. Ours is 91330282316889926U. Put it into the National Enterprise Credit Information Publicity System and you get the legal name, the registered address, the legal representative, the registration date and the business scope — the government's own record, not the supplier's brochure. A supplier who will not give you this code is not worth the next five checks.
This is the check a trading house fails. The registered scope distinguishes 生产 / 制造 (manufacture) from 销售 (sell) and 批发 (wholesale). A company whose scope says only sales and wholesale does not run a production line, whatever the website says. If the scope lists manufacturing, check that the registered address is the same place they are inviting you to visit.
Ask for a photograph of the original licence. Check three things: the name matches the one on the invoice, the address matches the one in the credit registry, and the licence has the official seal. A scanned copy with a translation stapled to it proves only that someone can use image software.
This is the other check a trading house fails. Call with no notice and ask to be walked from the raw material store to the packing line in one continuous shot. Ask them to pan to a window or a door and read the number on it — that pins the footage to a real address rather than a loop from someone else's plant. We take these calls at any hour, because we work from the building.
Finished goods can be bought in and photographed. Tooling cannot. Ask to see the mould or die for your part. If a supplier claims to make a part but has no tool for it, they are buying it in. This is also the question that tells you whether they can actually change anything for you later.
A logo on a webpage proves nothing; a number in the issuer's database does. Our staple guns carry the GS-Mark under approval 50571636, test mark 1111263764, issued by TÜV Rheinland — verifiable in Certipedia under our company name. If a supplier shows you a certificate, take the number and look it up yourself.
Whatever the first six checks say, the seventh is the one that costs money and settles it: a small paid run, signed off by your own QC before bulk starts. A real factory will agree to that order of events. One that wants the bulk deposit first is telling you something.