MBE Rules · Torts
Component-Part Makers
Component-part doctrine
The rule
A supplier of a non-defective component is not liable for defects in the integrated product unless the component itself was defective or the supplier substantially participated in the integration design.
In plain English
A supplier of a component part is generally not responsible for issues with the final product unless the part they supplied was defective on its own or they played a significant role in how the parts were combined. This means that if the final product fails, the supplier may not be liable if their component was fine.
Worked example
A company manufactures a car and uses brakes supplied by another company. The brakes are non-defective, but the car's design is flawed, leading to accidents. The brake supplier is not liable for the accidents because their component was not defective and they did not participate in the car's design.
Memory hook
Component suppliers are off the hook unless their part is faulty or they designed the mess.
The trap
Exams may present scenarios where students assume liability based solely on the final product's failure, overlooking the need for a defect in the component or substantial involvement in design.
How examiners test it
Questions often involve a fact pattern with multiple parties, testing students on distinguishing between component defects and design issues in integrated products.
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