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Browsing by Author "Albuquerque, Bruno"

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  • Stock market effects of corporate malpractices and misconduct: evidence from the short-seller Hindenburg
    Publication . Albuquerque, Bruno; Martins, António Miguel Valente; Moutinho, Nuno
    This study used event study methodology to examine the impact Hindenburg Research shortseller reports on targeted firms. The results show negative abnormal returns in firms when those reports reveal bad news about malpractices and misconduct. Our results show a higher negative stock market reaction to the Hindenburg reports when target firms are small, have higher leverage, higher Tobin’s Q, and corporate malpractice involves financial fraud. Our findings evidence that adverse information disclosed in the Hindenburg report led to a “torpedo effect”, resulted in sharp, immediate, and persistent share price drops.
    2025Journal article Open access Show more
  • Stock market effects of CrowdStrike IT outage on largest listed hotel companies
    Publication . Albuquerque, Bruno; Cró, Susana; Moutinho, Nuno; Martins, António Miguel
    This study analyses the short-term market effect of CrowdStrike IT outage in the 100 largest worldwide listed hotel companies. Using an event study methodology, the paper analyses how hotel companies are penalized by the market to the biggest IT disruption in history. Our results evidence a statistically significant negative reaction around the event date. This result is explained by the adverse impact caused by IT failures in the hotel’s business operations (reservation, payment, technical systems) and supply chain processes, which result in financial losses. We also observe a highest negative stock market reaction for hotel companies located in Western countries and for hotels with a low cyber risk rating. Finally, this study identifies hotel-specific characteristics that drive value during an IT outage. The research evidence that larger and more profitable hotel companies, with lower leverage and higher cyber risk ratings are more resilient to the adverse effects of IT outages.
    2025Journal article Open access Show more