Reconciling innovation and sustainability through the Triple Helix Twins: A coopetition perspective[Réconcilier innovation et soutenabilité à travers les Triple Helix Twins : une perspective de coopétition]

This study examines how knowledge spills over in innovation ecosystems to reconcile innovation and sustainability objectives through coopetition in the Triple Helix Twins (THT) model. Building on the knowledge spillovers, THT, and coopetition literatures, the paper investigates how industry, university, government, and public actors (U-I-G-P) strategically align their objectives, resources, and constraints through coopetitive mechanisms in complex products and systems industries. Adopting a systematic combining protocol, the study focuses on the French aerospace and energy industries through 27 semi-structured interviews complemented by secondary data from informants' organizations and industries. The findings show that knowledge spillovers in the THT model are implicitly oriented by coopetition along three interrelated mechanisms: a strategic alignment triptych, a continuous control feedback loop of knowledge, and conditional sharing shaped by strategic behaviors and path-dependency. These mechanisms determine how knowledge spills over between the U-I-G and the U-P-G helix, under which constraints, and with what consequences for sustainability alignment. A central insight is that limited public integration and selective spillovers from U-I-G to U-P-G may contribute to more fragmented forms of participation and to the emergence of more polarized narratives in ecosystem governance. Indeed, this paper demonstrates that knowledge does not circulates uniformly into an undifferentiated environment; rather, it spills over the two helices of the THT through coopetition mechanisms shaping the multi-level governance of innovation ecosystems. Managerially, it calls for more inclusive and differentiated public engagement to improve knowledge circulation, reduce greenwashing risks, and improve public debate's quality in complex products and systems industries.