論國家對股票市場為「漲跌幅限制」之憲法正當性與憲法界線

On the Constitutional Legitimacy and Limits of State-Imposed Price Limit Rules in the Stock Market

本文旨在探討國家對股票市場實施「漲跌幅限制」之憲法正當性與憲法界線。鑑於股票市場為民眾普遍參與之重要經濟活動，國家所採取之管制措施是否符合憲法之任務與界限，實屬值得關注之議題。本文首先介紹現行漲跌幅限制制度之內容與管制目的，並從憲法規範觀點，分析國家進行此項措施所應履行之憲法任務，進而討論經濟管制與金融監理制度之憲法意涵。
本文進一步從憲法學角度，檢視該制度對財產權與契約自由所造成之干預，並透過憲法一體性解釋，說明此種限制措施不得違背憲法所保障之市場經濟基本秩序。此外，本文依法律保留原則與比例原則進行合憲性審查，特別結合財務金融學實證研究，如「磁吸效應」（magnet effect）、市場波動性與資訊不對稱等，評估其作為冷卻機制之成效與正當性。
綜合分析結果，本文認為現行漲跌幅限制制度之法律位階過低，且管制效果存疑。建議應提高規範層級並強化民主正當性，並要求主管機關於比例原則之適當性與均衡性兩層面，持續參考財務金融學之最新研究成果，檢視其是否確實有助於穩定市場、降低投機與防範系統性風險。

This article examines the constitutional legitimacy and boundaries of the price limit mechanism implemented by the state in the stock market. Given the widespread participation of the general public in the securities market, the constitutionality of such regulatory measures has become an issue warranting serious attention. The study begins by introducing the content and regulatory objectives of Taiwan’s current price limit rules and analyzes the constitutional duties the state must fulfill when adopting such measures. It further explores the constitutional implications of economic regulation and financial supervision in this context.
From the perspective of constitutional law, this article investigates how price limits interfere with individuals’property rights and freedom of contract. It argues, through the method of integrative constitutional interpretation, that such restrictions must not contravene the foundational design of a market economy as protected by the Constitution. In addition, the article conducts a constitutionality review based on the principles of legal reservation and proportionality, incorporating findings from empirical studies in financial economics. Particular attention is given to the“magnet effect,”as well as issues of market volatility and information asymmetry, in assessing the actual effectiveness of the price limit regime as a cooling-off mechanism.
Based on the comprehensive analysis, the article contends that the current legal framework for price limits is inadequate in normative status and questionable in terms of regulatory efficacy. It recommends elevating the regulatory basis of such mechanisms to statutory law and enhancing their democratic legitimacy. Moreover, it emphasizes that competent authorities should, in accordance with the proportionality principle, continually evaluate the suitability and balance of the price limit system by integrating up-to-date empirical insights from the field of financial economics. These include evaluating whether such measures effectively stabilize markets, reduce excessive speculation, and mitigate systemic risks, especially in light of concerns such as price rigidity, increased volatility, and reduced liquidity.