<p>This postdigital marketization study examines how South Korea’s Artificial Intelligence Digital Textbook (AIDT) initiative formed, legitimized, and unevenly reconfigured an EdTech industry assemblage in public education. Drawing on Actor-Network Theory and ten semi-structured interviews with participants from the EdTech industry, it traces how this assemblage emerged through multiple interactions among human, non-human, material, and discursive actors, including government ministries, EdTech startups, textbook publishers, policies, documents, technologies, and regulations. The analysis identifies three overlapping phases in the process: pre-assembling in the post-Covid expansion of digital schooling; consolidation through the state-led materialization of AIDT; and reconfiguration through uneven authorization outcomes and classroom entry. It further shows how four key mediators—legal textbook status, speculative public funding, data governance, and personalization discourse—both enabled and destabilized the industry’s access to public schools. Rather than presenting the AIDT initiative as a straightforward narrative of educational privatization or a complete story of policy failure, the study argues that it produced a contingent and contested process of postdigital marketization through which the EdTech industry gained partial, reversible, and fragile access to public education. By shifting attention from policy assemblage to industry assemblage, the article highlights the unstable mediations through which state ambition, commercial interest, and reform discourse became temporarily aligned.</p>