In a letter to Dell shareholders, Icahn said a change in the voting procedure made it "almost impossible to win the battle" at Thursday's shareholder meeting on the plan led by company founder Michael Dell.
He was referring to a change which meant that only votes cast would be tallied, making the approval process easier. Shareholders not voting will no longer be counted as "no" votes.
The vote was delayed three times on concerns that shareholders might reject the plan, and the offer was increased by some USD 350 million to nearly USD 25 billion.
The 77-year-old Icahn has fought some of the roughest proxy battles in modern corporate history, ranging from the airline TWA to RJR Nabisco and Blockbuster Video. He also headed a shareholder revolt at Yahoo after the Internet giant rejected a takeover from Microsoft.
On Dell, Icahn said, "I realize that some stockholders will be disappointed that we do not fight on. However, over the last decade, mainly through 'activism' we have enhanced stockholder value in many companies by billions of dollars."
Michael Dell and his backers have claimed the struggling former number one computer maker needs to make major changes to keep up with the shifting tech landscape, and that this would best be done as a privately owned firm that is not subject to shareholder pressures.
