In recent decades, theorizing about societal and political transformations has become closely intertwined with claims about new modalities of knowledge production. Exemplary of these changes has been the remaking of the policy–science nexus. Traditional technocratic and hierarchical policy-making styles have been gradually reshaped by more horizontal participatory procedures in which “expert” knowledge is not synonymous with “scientific” knowledge. These developments imply recognition of feminist knowledge and academia as politically relevant “gender expertise” in many European countries, including Germany. However, in about 2005, public campaigns against the “ideology of gender” or “genderism” began to question the scientific character of gender research as a discipline.  This paper advances feminist approaches to the expertise–policy nexus by deploying the concept of political epistemologies and drawing on the insights from science and technology studies that have been moving it from a linear “knowledge utilization approach” towards a notion of co-production and boundary-crossing configurations. The “male-stream” shows that countries differ enormously with regard to the ways in which they institutionalize expertise and assess knowledge claims in political processes. This analysis explores the German political knowledge regime through the lens of such comparative typologies. It focuses on the period from 2000 onwards, which has been marked by major reform projects within the field of gender policies. This era has encompassed a double transformation: one from women and gender towards intersectionality and diversity as well as one represented by the shift in the contact zone between expertise and politics, developing from an expertise embedded primarily within government and public bodies into a horizontal web of advisory systems. Drawing on interview data and documentary analysis, this article considers the following questions: What institutional and epistemic mechanisms can account for Germany’s knowledge regime? What impact is anti-genderist mobilization having on political epistemology?