Calibration services for open-hardware tools
[@pearce2017Emerging Business Models for Open Source Hardware] argues that a possible business model for Open Hardware is to offer calibration services. For example, even if the design of a tool is open, there can still be value in certifying its accuracy. Non-open processes, trademarks, etc. all build into this direction. Even if the device can be cloned, one still keeps the key of the certification.
This practice is not exclusive of open hardware, though. See: How Phillips protected IP by not outsourcing key manufacturing components
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