Purpose This paper describes the case of how the Danish beer manufacturer, Carlsberg, developed the Green Fiber Bottle as part of its sustainability program through an open innovation approach in collaboration with complementary partners. It thereby illustrates how a grand challenge associated with sustainability can be effectively addressed through open innovation and reveals the opportunities and challenges that emerge in that context. Design/methodology/approach The paper summarizes some key elements of the case and, in particular, discusses some of the lessons learned, which can be further explored in future research, practice, and policy. Findings The case suggests a number of key issues that are relevant when attempting to address grand challenges, in general, and sustainability in the food and beverage (F&B) industry, in particular, namely: leveraging open innovation in the face of sustainability as a grand challenge; sustainability beyond a solid business case; opportunities and challenges in the face of new business models; the importance of early wins for addressing societal challenges for signals and scaling; and the importance of the Nordic context and long-term vision. Originality/value The case describes a recent (and to some extent still ongoing) initiative of how a particular F&B company has explored new approaches to developing its sustainability program. Therefore, it highlights some of the unique characteristics of this case. This paper also lays the groundwork for the establishment of "Sustainable Open Innovation" as a domain in its own right.