This policy brief aims to explain the open source silicon approach in terms of its importance for semiconductor research and development as well as its industrial integration in Europe. It will examine the background of this approach and how it relates to the semiconductor value chain, as well as its weaknesses and strengths and their consequences for Europe: After an overview of the open source silicon landscape, a SWOT analysis will be presented to identify how the approach of open source silicon can be leveraged to strengthen the European semiconductor industry. The knowledge production process at the basis of this brief involved targeted research, expert interviews and insights gained from ALLPROS.eu workshops and webinars.