Reaction of stocks to administrative sanction announcements: The BIST 100 case
Abstract
The purpose of this study is to determine the reaction of companies in the BIST 100 index in the case of administrative sanctions by the Capital Markets Board of Türkiye. For this purpose, 42 violations by 35 companies between 2013 and 2022 were evaluated. The event study methodology was used, and both parametric (Patell Z, Cross-sectional t-test, Standardized Cross-sectional t-test, and Skewness-adjusted t-test) and nonparametric (Generalized Sign and Rank tests) approaches were utilized. The event study methodology was as follows: The market model, which measures the returns of stocks to the returns of the market throughout a 200-day estimation window, is employed to determine CAARs. A 21-day period was established to monitor market reactions. The empirical outcomes consistently demonstrate negative CAARs, and in the [−10, +10] and [−5, +5] windows, statistically significant CAAR values are particularly evident (CAAR =-5.73% and −3.92%, respectively). Thus, the market responds negatively to the news of administrative sanctions. By applying various statistical approaches, this study contributes to the literature by offering solid empirical evidence on the short- and long-term effects of administrative sanctions on the market. It highlights the market’s responsiveness to corporate misconduct in an emerging market setting like Türkiye.
Keywords
References
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Details
Primary Language
English
Subjects
Business Administration
Journal Section
Research Article
Authors
Publication Date
December 31, 2025
Submission Date
January 28, 2025
Acceptance Date
October 14, 2025
Published in Issue
Year 2025 Volume: 54 Number: 3
APA
Erbuğa, G. S. (2025). Reaction of stocks to administrative sanction announcements: The BIST 100 case. Istanbul Business Research, 54(3), 408-426. https://doi.org/10.26650/ibr.2025.54.1628617
AMA
1.Erbuğa GS. Reaction of stocks to administrative sanction announcements: The BIST 100 case. IBR. 2025;54(3):408-426. doi:10.26650/ibr.2025.54.1628617
Chicago
Erbuğa, Gökçe Sinem. 2025. “Reaction of Stocks to Administrative Sanction Announcements: The BIST 100 Case”. Istanbul Business Research 54 (3): 408-26. https://doi.org/10.26650/ibr.2025.54.1628617.
EndNote
Erbuğa GS (December 1, 2025) Reaction of stocks to administrative sanction announcements: The BIST 100 case. Istanbul Business Research 54 3 408–426.
IEEE
[1]G. S. Erbuğa, “Reaction of stocks to administrative sanction announcements: The BIST 100 case”, IBR, vol. 54, no. 3, pp. 408–426, Dec. 2025, doi: 10.26650/ibr.2025.54.1628617.
ISNAD
Erbuğa, Gökçe Sinem. “Reaction of Stocks to Administrative Sanction Announcements: The BIST 100 Case”. Istanbul Business Research 54/3 (December 1, 2025): 408-426. https://doi.org/10.26650/ibr.2025.54.1628617.
JAMA
1.Erbuğa GS. Reaction of stocks to administrative sanction announcements: The BIST 100 case. IBR. 2025;54:408–426.
MLA
Erbuğa, Gökçe Sinem. “Reaction of Stocks to Administrative Sanction Announcements: The BIST 100 Case”. Istanbul Business Research, vol. 54, no. 3, Dec. 2025, pp. 408-26, doi:10.26650/ibr.2025.54.1628617.
Vancouver
1.Gökçe Sinem Erbuğa. Reaction of stocks to administrative sanction announcements: The BIST 100 case. IBR. 2025 Dec. 1;54(3):408-26. doi:10.26650/ibr.2025.54.1628617