This essay provides a conceptual contribution to the understanding of solidarity rights and their relevance in an increasingly interconnected world, focusing on the common heritage of humanity. The analysis lies at the intersection of human rights with international heritage law, two areas that have developed along different historical trajectories. Recently policymakers and scholars have emphasized their interrelationships, suggesting that heritage is a human right, that human rights provide a framework for heritage protection, and that human rights themselves are a common heritage of humanity. Yet less attention has been given to the fact that the common heritage of humanity is also a principle of international law. As a legal formulation of the stewardship philosophy known in many religions and cultures, the common heritage of humanity embodies altruistic, equalitarian, and moral ideals. It is at the same time a controversial principle, because it introduces humanity as subject of law and triggers duties of solidarity and commitments that challenge state sovereignty. Drawing on the common heritage of humanity as principle of law in different historical and legal contexts, this essay explores its potential to illustrate the underlying message of solidarity rights and the implications of solidarity rights.