From Barron's Tech Trader Daily blog:
Shares of Symantec (SYMC) are up $1.76, or 13.4%, at $14.94 after the company this morning said its CEO, Enrique Salem, stepped down after the board of directors decided it was best to have an executive change given that the company is “underperforming against its opportunity,” in the words of incoming CEO Steve Bennett, who is the company’s chairman and formerly CEO of Intuit (INTU)....MOREOne of the few CEO-related stock moves that was nastier was Gulf+Western (now Paramount Communications).
The day CEO Charles Bluhdorn died in 1983 the stock closed at $9.
One week later: $12.375.
Occidental Petroleum used to trade up every time CEO Armand Hammer got sick.
As the New York Times reported the day after of Hammer's 1990 death:
...Reflecting a belief that any changes would benefit the company's flagging stock price, shares of both Occidental and IBP rose in heavy trading after the news of Dr. Hammer's death. [ Obituary, page D20. ]
Occidental's shares rose $1.875 on the New York Stock Exchange today, to $22.625. The issue was the most active of the day, with 8.1 million shares changing hands...That was $500,000,000 in market cap back when a half-billion was real money.
Still, it's not 13%.