Who Owns Your LSR Mold? The Tooling Clauses Most Buyers Forget Until It's Too Late

Most silicone part buyers spend weeks comparing mold quotes — steel grade, cavitation, lead time, price. Very few spend ten minutes on the question that matters most when something goes wrong: who actually controls the mold after you pay for it?

In OEM manufacturing, the mold usually stays at the supplier's factory. That is normal and efficient. But it also means your most expensive production asset sits in someone else's building, under someone else's maintenance, with someone else's records. If the relationship ends, prices rise, or the factory changes ownership, the paperwork you signed on day one decides whether you can move production in two weeks — or start over from zero.

Three common ownership models

None of these is wrong. The problem is when the buyer assumes model 1 but the contract only says "mold fee: USD X." A payment line is not an ownership clause.

What should be in writing

1. A clear ownership statement
State that the mold, including all inserts, cavities, the cold runner / valve gate system, and spare parts paid for by the buyer, is the buyer's property. For LSR molds this detail matters: the cold runner block and needle-valve system are a significant share of the tooling cost. If the contract only covers "the mold," some suppliers will treat the cold runner as their own equipment.

2. Identification on the tool
Ask for a nameplate on the mold base showing your company name, mold number, and "Property of [Buyer]." It sounds trivial, but it makes ownership visible to anyone who handles the tool — including a new factory manager years later.

3. Drawings and data handover
Define what you receive: final 3D mold design, 2D assembly drawings, insert drawings, cooling/heating layout, and a bill of materials for wear parts. Without these, even an owned mold is hard to repair elsewhere.

4. Expected mold life and warranty
Specify the target shot life (for example, by referencing an SPI mold class) and what the supplier must repair or replace free of charge within that life. Separate normal wear items (seals, valve needles, heater bands) from structural failures.

5. Maintenance and shot records
Require a shot counter on the mold and a maintenance log you can request at any time: cleaning cycles, parts replaced, repairs, and dates. This record is also your best evidence if a quality dispute arises.

6. Transfer conditions
This is the clause buyers regret skipping. Define:

• Notice period for mold release (e.g., 15–30 days)
• Condition at handover — cleaned, rust-protected, last-shot samples included
• Who pays packing, export documents, and freight
• That the mold cannot be withheld over unrelated commercial disputes

7. Storage and insurance
Who is responsible if the mold is damaged by fire, flooding, or mishandling while stored at the factory? Agree on it before it happens.

8. Use restrictions
The supplier should not use your mold to produce parts for anyone else, and should not modify it without written approval.

LSR-specific points worth checking

LSR molds differ from thermoplastic molds in ways that affect ownership and transfer:

• Heated mold, cold runner. The mold runs hot (typically 150–200 °C) while the runner stays cold. Temperature controllers and wiring standards should be documented so another factory can run it.
• Valve gate control. Needle-valve timing and the controller interface must match the receiving machine. Ask for the settings sheet.
• Process parameters. Ownership of the mold is more useful when you also hold the validated process window — injection speed, cure time, mold temperature, demold method. Ask for a process sheet as part of PPAP or first article approval.

A short pre-signing checklist

How TYM handles tooling

At TYM, customer-paid LSR molds are documented as customer property, including the cold runner system. Each tool carries a mold card with its maintenance history, and process parameters are recorded at sample approval so the mold can be supported long-term — whether production stays with us or not.