The international governance landscape on climate change mitigation is increasingly complex across multiple governance levels. Climate change mitigation initiatives by non-state stakeholders can play an important role in governing global climate change and contribute to avoiding unmanageable climate change. It has been argued that the UNFCCC could and should play a stronger role in ‘orchestrating’ the efforts of these initiatives within the wider climate regime complex and thus inspire new and enhanced climate action. In fact, the Lima-Paris Action Agenda supporting cooperative climate action among state and non-state actors was supposed to be a major outcome of COP21. There is little doubt that successful mitigation initiatives can create a momentum for climate protection. What is missing, is a systematic analysis of how this momentum can feed back into the UNFCCC negotiation process, inspiring also enhanced and more ambitious climate mitigation by states in future iterations of the cycle of nationally determined contributions under the Paris Agreement. This paper aims to close this gap: building on a structurational regime model, the article  develops a theory of change of how and through which structuration channels non-state initiatives can contribute to changing the politics of international climate policy;  traces existing UNFCCC processes and the Paris Agreement with a view to identifying entry points for a more direct feedback from non-state initiatives; and  derives recommendations on how and under which agenda items positive experiences can resonate within the UNFCCC negotiation process.