Exxon then followed with the acquisition of Mobil, and Chevron bought Texaco.
He once offered to buy Texaco for $60 a share.
Chevron bought Texaco for $36 billion in 2000.
Frank P. Knuettel of Prudential-Bache Securities advised clients to buy Texaco at $28.50 in late 1985 when the stock came under severe pressure.
This is not the first time Chevron has tried to buy Texaco.
Mr. Icahn wants to buy Texaco, pay for the purchase largely by selling some assets and reorganize the remaining businesses.
In spring 1999, Chevron tried to buy Texaco for $37.5 billion, which Texaco rejected as too low.
Mr. Icahn, who has made an offer to buy Texaco, was trying to elect himself and four allies to Texaco's 14-member board.
A24 Carl C. Icahn offered to buy Texaco for $60 a share, valuing the nation's third-largest oil company at about $14.6 billion.
Why not buy both Pennzoil and Texaco?