Tools for the clinical examination have not fundamentally evolved since the invention of the stethoscope by René Laennec in the nineteenth century. However, three decades ago, the medical community started to consider repurposing ultrasound scanners to improve physical examinations. Adequate training programs are required to change the clinical examination paradigm, but a broad community of health care professionals could not be created due to the very high price of portable ultrasound scanners available on the market. In this paper, we study an open-source Medtech community that aims to improve diagnosis orientation in hospitals and medically underserved areas worldwide. They are designing an echo-stethoscope -a portable ultrasound scanner- that would be affordable in low and middle-income countries. The variety of expertise pooled to achieve this objective puts this knowledge common (KC) at the crossroads of open source software, open-source hardware, and medical communities unique. Unlike typical KC outcomes, an ultrasound probe is a physical object. Development and innovation in the physical world bring social dilemmas that the community has to overcome, in particular, restrictions in terms of openness. Our study uses the Governing Knowledge Common Framework, a modified Institutional Analysis, and Development framework, to untangle the interactions between resources, participants, and governance structures. Our research describes why and how the creation of a physical object subject to medical regulation influences the evolution and governance of the KC. We provide evidence that KCs coupled with effective project portfolio management(PPM), are effective and resilient institutional arrangements in Medtech project settings. They are flexible and scalable enough to protect and grow shared knowledge throughout the product development process.