Calls to advance the democratization of sustainable development negotiations have recently proliferated. However, the participatory schemes set up by international organizations and governments have fallen short of answering to academic and empirical demands for global democracy, in particular by excluding the most marginalized actors from policymaking. Deliberative democrats argue that discursive representation may, in some contexts, overcome the shortcomings of actor-based representation and advance global democracy. To what extent, then, does discursive representation effectively contribute to the democratization of global policymaking by representing diverse interests, including those of marginalized actors? By performing a qualitative–quantitative discourse analysis of 122 primary documents issued during the formal sessions of negotiations of the Open Working Group on the Sustainable Development Goals, this article explores the extent to which different sustainability discourses that evolve in the public space got represented within authoritative circles of decision-making. While the negotiations on the Sustainable Development Goals involved more than ten million civil society voices and resulted in an agreement that claims to “transform our world” and “leave no-one behind,” the study shows that discursive representation was biased toward a progressive sustainability discourse, depicting a state-centric orientation of equity and responsibilities to address global sustainable development challenges. Besides, the coalitions that emerged between state and non-state actors on alternative sustainability discourses failed to increase the saliency of the interests of marginalized actors in the shaping of the goals. As the understandings of transformation and inclusiveness conveyed in the negotiations were biased toward the interests of the most represented actors in the Open Working Group, the article reveals that in the context of the negotiations on the Sustainable Development Goals the effectiveness of discursive representation in democratizing global policymaking was eventually limited.