IP protection when sourcing injection molds from China is a contract and file-control problem, not a watermark on a PDF. OEMs who email native CAD to five traders, then ask for an NDA after the quote, have already multiplied copies. You cannot eliminate risk. You can reduce who has the files, what they may do with the tool, and how you get steel and data back.
This guide is practical OEM hygiene: NDA timing, what to send, ownership, and dual-source without cloning your own leak. Legal advice for your jurisdiction is still yours. Commercial ownership: mold ownership. Supplier screen: manufacturer guide.
Control the copies before the NDA theater
| Practice | Why |
|---|---|
| NDA before native CAD; STEP + 2D to a shortlist of 3 | Fewer inboxes |
| Watermark 2D with company + date + “quote only” | Deters casual forward; not forensic proof |
| Do not send electronics schematics with the plastic RFQ | Need-to-know |
| Named factory, not a trader chain | Supplier types |
| Audit who can open the server folder | Factory audit |
An NDA with a trading company does not bind the unnamed tool shop. If you need China tooling, contract the floor that cuts steel — in-house maker checklist.
Own the steel and the design files
- Mold is yours after final payment; storage and export written
- 3D tool design + electrode/insert drawings as deliverables
- No “we keep the design as our IP” on a tool you funded
- Spare inserts and hot-runner specs so you can transfer — mold transfer
Put file delivery on the same milestone as T1, not “upon request.” Quote lines: how to read a quote.
What still leaks (be honest)
A determined copier can reverse a shipped part. NDAs help with contractors you can find and sue. They do not stop a third party who buys your product. Design in features that are hard to copy cheaply (texture, internals, firmware) if the business needs it — that is product strategy, not a clause.
Dual-source after a stable T1, with your files, not two factories sharing one leaked STEP: dual sourcing.
RFQ and PO clauses worth having
- Confidentiality + no use except to quote/make your parts
- No subcontract without written approval
- Ownership of mold, electrodes, and design data
- Return or destroy quote files if you do not award
- Photos of your parts not for their Alibaba catalog without approval
China vs domestic is sometimes an IP comfort choice as much as a cost choice: China vs domestic. TCO still applies: TCO.
How Deuchi handles files
Deuchi quotes from a short RFQ list, treats CAD as customer confidential, and writes mold and design-file ownership into the program. We do not need your full product BOM to mold a housing. Contract manufacturing and mold build; start at contact.
FAQ
Is a China NDA enforceable?
It can be, if the party is real and the contract is drafted for that venue. Enforceability is not the same as “they cannot copy a part they can buy.” Use NDA plus file hygiene plus ownership.
Should we patent before RFQ?
If you were going to file, file before broad disclosure. Patent strategy is counsel’s job; RFQ hygiene is yours this week.
Can we send STL only?
STL is a mesh. Fine for a concept screen; bad for a production quote. Use STEP after NDA with the shortlist.
Do we register the mold in China?
Customs/IP recordal and mold marking are country-specific. Ask counsel. Commercially, mark the tool as your property and keep the files.
Next step: Contact Deuchi under NDA with STEP/2D when you are ready for a DFM quote from one manufacturer, not a blast to a dozen inboxes.