控股股东股权质押与股价波动——基于公司创新投入的中介效应研究

Pledge of Controlling Shareholders’ Share and Stock Price Fluctuation:Research on the Mediation Effect based on the Company’s Innovation Investment

近些年,控股股东股权质押越来越盛行,其带来的影响值得关注。为研究控股股东个人的股权质押行为对市场上股票价格波动所形成的影响及其具体的中介机制,采用OLS回归分析法,选择了除金融行业以外的所有A股上市公司为研究对象,选取2007—2017年作为样本区间进行研究。研究表明,与没有控股股东股权质押行为的公司相比较,有控股股东股权质押行为的公司对股价波动的影响会更大,同时股东进行质押的比例越高,对上市公司股价波动的影响幅度就越大,从实质上验证了控股股东的个人股权质押行为确实会加剧公司股价波动的风险。另外,无论是股东个人的股权质押行为与公司的创新投入还是公司的创新投入与股价波动的关系,两者都是负相关,并且发现创新投入在控股股东股权质押与上市公司股价波动之间发挥着显著的中介作用。进一步把公司创新投入分为实质性创新和策略性创新两个方面,发现实质性创新发挥的中介效应更大。研究既可以为政府部门监督和管理上市公司股东恶意质押股权的不良行为,从而防止股市震荡提供理论与实证的支撑,还能为公司对创新的投入和投资者的投资策略提供方向。

In recent years, the share pledge of controlling shareholders has become more and more popular, and its impact is worthy of attention. In order to study the influence of individual controlling shareholder′s share pledge behavior on the stock price fluctuations in the market and the specific intermediary mechanism, the article adopts OLS regression analysis method and selects all A-share listed companies except the financial industry as the research objects. The 2007—2017 period was used as the sample interval for research.Studies have shown that, compared with companies that do not have a controlling shareholder′s share pledge, a company with a controlling shareholder′s share pledge will have a greater impact on stock price fluctuations. At the same time, the higher the percentage of pledged by shareholders, the greater the impact on the fluctuation of the listed company’s stock price, which substantively verifies that the controlling shareholder’s pledge of personal share will indeed aggravate the risk of the company’s stock price fluctuations.In addition, whether it is the relationship between the individual shareholder′s share pledge behavior and the company′s innovation investment or the company′s innovation investment and stock price fluctuations, both are negatively correlated, and it is found that innovation investment plays a significant intermediary role between the controlling shareholder′s share pledge and the stock price fluctuations of listed companies. The article further divides the company’s innovation investment into substantive innovation and strategic innovation, and finds that substantive innovation exerts a greater intermediary effect. Finally,the research can not only provide theoretical and empirical support for government departments to supervise and manage the malicious pledge of share by shareholders of listed companies so as to prevent stock market fluctuations, but also provide direction for the company’s investment in innovation and investors’ investment strategies.