The Impact of Regulatory Fines on Stock Performance: Evidence from Turkish Capital Markets

Yıl 2026, Cilt: 44 Sayı: 1, 156 - 190, 23.03.2026

Kartal Somuncu

https://doi.org/10.17065/huniibf.1691675

https://izlik.org/JA52UR44HP

Öz

This study examines the short-term market effects of administrative fines imposed on corporations by the Capital Markets Board of Türkiye (CMB) on the stock returns of the sanctioned firms. Regulatory sanctions generate not only legal and financial consequences but also significant information shocks that update investors’ information sets and influence expectations regarding firm value. The aim of the study is to analyze whether administrative fines are priced by investors as a deterrent mechanism or as a public signal that reduces information asymmetry.The empirical analysis is based on 1,091 administrative fine announcements directed exclusively at corporations and publicly disclosed in the CMB’s weekly bulletins over the period 2013–2024. Using the event study methodology, expected returns are estimated with the market model, and abnormal returns as well as cumulative average abnormal returns are calculated over an event window of [-10, +10] trading days. The findings indicate that, for the full sample, market reactions to fine announcements are limited and transitory; however, during the 2019–2024 period, administrative fines generate strong and persistent negative price reactions. These results suggest that, in the more recent period, CMB sanctions have been perceived by investors as stronger signals of corporate risk and reputational loss.

Anahtar Kelimeler

Regulatory Enforcement , Administrative Fines , Stock Price Reaction , Event Study Methodology , Emerging Markets

Etik Beyan

All data used in this study were systematically collected from the weekly bulletins published on the official website of the Capital Markets Board of Turkey (www.spk.gov.tr). These data are publicly available and can be accessed without the need for permission from any individual or institution. No fees were paid for the acquisition or use of the data. In this context, all datasets employed in the study were obtained and analyzed in accordance with the principle of transparency, using publicly accessible sources. Therefore, the research process fully complies with ethical principles and the standards of academic integrity.

Destekleyen Kurum

Destekleyen herhangi bir kurum bulunmamaktadır.

İdari Para Cezalarının Hisse Senedi Getirileri Üzerindeki Etkisi: Türkiye Sermaye Piyasalarından Kanıtlar

https://izlik.org/JA52UR44HP

Öz

Bu çalışma, Sermaye Piyasası Kurulu (SPK) tarafından şirketlere uygulanan idari para cezalarının, ilgili şirketlerin hisse senedi getirileri üzerindeki kısa vadeli piyasa etkilerini incelemektedir. Düzenleyici yaptırımlar, hukuki ve mali sonuçlarının yanı sıra yatırımcıların bilgi setini güncelleyen ve firma değerine ilişkin beklentileri etkileyen önemli bilgi şokları üretmektedir. Çalışmanın amacı, idari para cezalarının yatırımcılar tarafından caydırıcı bir mekanizma mı yoksa bilgi asimetrisini azaltan kamusal bir sinyal mi olarak fiyatlandığını analiz etmektir.
Ampirik analiz, SPK haftalık bültenlerinde 2013–2024 döneminde kamuya açıklanan ve yalnızca şirketlere yönelik 1.091 idari para cezası duyurusuna dayanmaktadır. Olay çalışması yöntemi kullanılarak beklenen getiriler piyasa modeliyle tahmin edilmiş; anormal getiriler ve kümülatif ortalama anormal getiriler [-10, +10] işlem günü penceresinde hesaplanmıştır. Bulgular, tüm örneklem için piyasa tepkilerinin sınırlı ve geçici olduğunu, ancak 2019–2024 döneminde idari para cezalarının güçlü ve kalıcı negatif fiyat tepkileri yarattığını göstermektedir. Bu sonuçlar, son dönemde SPK yaptırımlarının yatırımcılar tarafından daha ciddi bir kurumsal risk ve itibar kaybı sinyali olarak algılandığını ortaya koymaktadır.

Anahtar Kelimeler

Düzenleyici Yaptırım , İdari Para Cezaları , Hisse Senedi Fiyat Tepkisi , Olay Çalışması Yöntemi , Gelişmekte Olan Piyasalar.

Etik Beyan

Bu çalışmada kullanılan tüm veriler, Sermaye Piyasası Kurulu'nun (www.spk.gov.tr) resmi internet sitesinde yayımlanan haftalık bültenlerden sistematik bir şekilde toplanmıştır. Bu veriler kamuya açık olup, herhangi bir kişi ya da kurumdan izin alınmasına gerek kalmaksızın erişilebilmektedir. Veri edinimi veya kullanımı için herhangi bir ücret ödenmemiştir. Bu bağlamda, çalışmada kullanılan tüm veri setleri şeffaflık ilkesine uygun olarak kamuya açık kaynaklardan elde edilmiş ve analiz edilmiştir. Dolayısıyla araştırma süreci, etik ilkelere ve akademik dürüstlük standartlarına tam anlamıyla uygun şekilde yürütülmüştür.

Destekleyen Kurum

Destekleyen herhangi bir kurum bulunmamaktadır.

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