["Business Strategy and the Environment, Volume 35, Issue 4, Page 5490-5513, May 2026. ", "\nABSTRACT\nOrganizations increasingly innovate their business models (BMs) toward sustainability to maintain competitiveness and comply with regulations. Sustainable business model innovation (SBMI) requires decision‐makers to identify ecological and social opportunities while balancing economic goals. However, BMs as mental models are guided by experiences and cognitive biases, influencing the recognition of SBMI opportunities. Research on how mental models affect opportunity recognition for SBMI in incumbent firms remains limited. We examine how boundary objects enhance opportunity recognition in SBMI. Through a single case study in the industrial automation sector, we identify significant variations in decision‐makers' mental models and demonstrate how boundary objects mitigate cognitive barriers. Findings highlight differences between managers with diverse professional backgrounds and propose measures to foster the identification of suitable opportunities in SBMI. This study contributes to SBMI research by identifying micro‐level cognitive constraints and offers practical recommendations to improve strategic decision‐making in contexts of sustainability innovation.\n"]