<p>Recent posthumanist discussions in business ethics emphasize that humans and nonhumans are entangled in a network and that humans can no longer be exclusively at the center of business activities, as humanism postulates. With this insight, we turn to stakeholder theory, which has become a prominent approach in integrating sustainability into management research. While stakeholder research has offered significant starting points into acknowledging various nonhuman beings and entities––such as animals, plants, and ecosystems––as stakeholders, a systematic understanding of nonhumans in stakeholder theory is lacking. We seek to advance theorizing on nonhuman nature stakeholders by examining how they can be conceptualized and categorized. We present a conceptualization with two dimensions: first, humanism and posthumanism as normative cores for stakeholder inclusion and, second, distant and intertwined connections to a firm’s main activities. Based on these dimensions, we suggest four categories of nonhuman nature stakeholders: unacknowledged, resource, protected, and partner. We also discuss the role of intermediaries in the firm–nonhuman stakeholder interface. The study adds to recent research by providing a theoretically and conceptually integrative categorization that includes various kinds of nonhumans and by advancing the inclusion of nonhuman stakeholders in stakeholder theory. In doing so, we challenge the prevailing human-centric view of stakeholder theory and illuminate the various ways in which nonhumans are and can be included in firm activities. We hope to inspire future research on nonhumans in stakeholder theory and business ethics.</p>