At the end of 2016, the Swedish petroleum and biofuel company Preem applied for an environmental permit to convert high-sulfur bunker oil to low-sulfur petrol and diesel at Preemraff Lysekil. Something that required an expansion of the refinery. The process ended abruptly in September 2020 when Preem chose to withdraw their application. In connection with the process, two actor coalitions were formed, with one being for an expansion and the other against. Both coalitions had the explicit goal of reducing greenhouse gas emissions and preventing climate change. The difference, however, was their view on whether this could be achieved thanks to an expansion of Preemraff Lysekil, or if it could only happen without it. Through their actions the coalitions have tried to influence the policy process in a direction that is desirable for them. This study aims to systematically map the coalitions and their actions and contribute to a deeper understanding of their actions and impact on the process of the planned expansion project of Preemraff Lysekil. The study is designed as a qualitative case study and is based on The Advocacy Coalition Framework (ACF), which can be used to explain and understand beliefs and policy change when multiple actors are involved in a policy process. According to the ACF, actors who share similar policy core beliefs come together in coalitions to increase the chances of policy change. The study also uses urban regime theory to understand the informal and unspoken agenda between Preemraff Lysekil and Lysekil municipality. The results from previous research show several common denominators with the Preemraff Lysekil case. The analysis shows that the actors who were against an expansion had similar deep core beliefs and consistent policy core beliefs, they also had a consensus on how the policy change should be implemented. They have tried to influence the process by appealing court decisions and tried to get the Swedish government to take over the assessment of the application, which also happened. The analysis shows that the actors who were in favor of an expansion had more dispersed deep core beliefs but were consistent in their policy core beliefs and secondary beliefs. They have made attempts to stop the government from taking over the case from the court. As these attempts have been unsuccessful, they instead tried to get the government to allow an expansion. By using different forms of resources, both coalitions have tried to get the public and decision-makers to support their own proposal for policy change, with varying results. What ultimately led Preem to withdraw the application is not clarified. Maybe the pressure from those who were against an expansion became too powerful, maybe the COVID-19 pandemic left such a big mark on international production chains and the global market that an expansion was no longer profitable. There is also a possibility that Preem's decision is based on both parts, but we will probably never know.