分期分級董事會制度與公司股價暴跌風險

Staggered Board and Firm-Specific Stock Price Crash Risk

本研究旨在探討公司實施分期分級董事會制度對於公司股價暴跌風險的影響。股價暴跌會對企業及其投資者帶來巨大的財務損失，是以探討有效減少該風險的公司治理機制實為一重要議題。我們以1999年至2018年間美國上市公司為研究樣本，並利用公司股票價格建構三種衡量股價暴跌風險的指標進行分析。實證結果發現，公司實施分期分級董事會制度，對於股價暴跌風險有顯著的負向影響。此結果顯示，實施該制度有助於提升公司治理品質，進而降低公司所面臨的股價暴跌風險。再者，研究結果亦發現，若公司的審計委員會規模較大、機構投資人持股比例較高、或是公司年齡較為年輕，則實施該制度對股價暴跌風險的降低效果會更為顯著。這些結果強調了分期分級董事會制度在不同公司治理結構中的影響性，企業應積極推行分期分級董事會制度，以強化公司治理，提升股價穩定性。此外，企業在制定治理架構時，應考慮審計委員會的規模、機構投資人的持股比例等因素，以儘可能降低股價暴跌風險，從而保障公司和投資者的利益。

This study investigates the effect of staggered board implementation on the risk of stock price crashes. We consider data from companies that were publicly traded in the United States from 1999 to 2018 and employ three indicators derived from stock prices to measure the risk of stock price crashes. Our empirical results reveal that implementing staggered boards significantly negatively affects the risk of stock price crashes. This evidence suggests that staggered boards enhance corporate governance quality, thereby reducing the likelihood of stock price crashes. Furthermore, we find that staggered boards are more effective at reducing crash risk in younger companies and in companies that have larger audit committees or greater institutional investor ownership. These findings underscore the importance of staggered boards within corporate governance structures and suggest that firms should actively consider implementing staggered boards to strengthen their governance and enhance their stock price stability. Additionally, when designing governance frameworks, companies should consider factors such as audit committee size and the level of institutional ownership to minimize the risk of stock price crashes and thereby safeguard the interests of both the company and its investors.