The unseen guardian: News co-mention and stock market manipulation

• This study shows that news co-mention significantly reduces the likelihood of stock market manipulation. • The effect is identified using high-frequency trading data and media coverage collected via distributed web crawlers. • News co-mention curbs manipulation primarily in continuous trading, but not in opening or closing price manipulation. • The mechanism operates through enhanced disclosure quality, strengthened CSR and internal governance, and amplified external media scrutiny. • The effect is more pronounced in firms with financially trained or overconfident CEOs, fewer female leaders, and weaker external monitoring. Drawing on high-frequency trading data and media coverage gathered via distributed web crawlers, this study investigates the impact of news co-mention on stock market manipulation. The findings indicate that news co-mention can effectively curb stock market manipulation. Specifically, this effect is observed only in continuous trading price manipulation, rather than in closing or opening price manipulation. Moreover, news co-mention exerts its influence by enhancing corporate transparency and social responsibility, bolstering internal governance, and by increasing general media coverage, thereby reducing market manipulation. This effect is more pronounced in companies with CEOs who have financial backgrounds, fewer female leaders, overconfident CEOs, and those facing less external scrutiny.