Deepwater Horizon oil spill

: stock performance effects on the energy industry

Abstract

This dissertation investigates the financial implications of the largest marine oil spill in history (Deepwater Horizon oil spill) on the Oil and Gas and Alternative Energy industries. Employing event study and regression methodologies, the analysis spans US and European markets to assess intra-industry and cross-industry effects, with a focus on the role of Gulf of Mexico exposure in driving abnormal stock returns. Findings confirm significant negative market reactions for BP and its partners, with severe negative cumulative abnormal returns reflecting strong intra-industry contagion. The research further highlights the disproportionate impact of negative news on market reactions compared to positive developments, suggesting investors tend to overreact to adverse events. Additionally, exposure to the Gulf of Mexico during the spill was identified as a key driver of abnormal returns. The study provides key insights for stakeholders in assessing financial risks associated with environmental disasters and offers a foundation for further exploration into long-term industry ramifications, such as regulatory impacts and shifts in energy policy.

Date of Award	29 Jan 2025
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Jörg Stahl (Supervisor)