Purpose: The purpose of this study is to identify incentives and discouragements thus providinga better understanding of how metal processing companies could set their Scope 3 boundary. Method: To achieve the purpose of the study, a qualitative case study with an inductive approach was used. The studied company was a global metal processing company that was working towards setting a Scope 3 boundary, and the data consists of semi-structured interviews that were gathered from both internal and external stakeholders. Findings: Firstly, the findings presented, highlight incentives that affected companies in the metal processing industry to pursue setting a Scope 3 boundary, namely incentives that are categorised into 1) Improved corporate environmental reputation, 2) Increased competitive advantage, and 3) Financial gains. The discouragements found were categorised into 1) High uncertainty, 2) Immature industry/technical solutions, and 3) Low influence outside of the organisational boundary. These incentives and discouragements were analysed to show how they affected the Scope 3 boundary. This resulted in an industry-specific guideline on how companies in the metal processing industry could set their Scope 3 boundary. Theoretical contribution: The findings prolong earlier research by defining incentives and discouragements in a Scope 3 context. A theoretical contribution from this study was that regulations might inhibit some of the Scope 3 incentives. The findings indicate that drivers to benchmark against other stakeholders, such as differentiating from competitors and improved corporate sustainable reputation. A non-regulatory market environment is, therefore, fostering these incentives, which could be useful to acknowledge in further studies in a Scope 3 context. Practical implications: This study provides an enhanced understanding of how metal processing companies can set their Scope 3 boundary based on what set of incentives or discouragements that drives them. It is also important for companies to understand incentives and discouragements that may change (e.g., regulations towards Scope 3 emissions) in time, which would result in different Scope 3 boundaries. Also, this understanding of what incentives and discouragementsaffecting the boundary-setting could benefit policymakers in their work improving the Scope 3 discouragements.