The two sides traded barbs Monday in the latest round in the ongoing tussle between the e-commerce company and the activist investor who wants to split it in two.
Icahn and eBay began their dispute in January, when Icahn disclosed a less than 1 percent stake in the company.
He wants eBay to spin off its PayPal mobile commerce arm, which is growing revenue faster than the rest of the company. EBay, on the other hand, strongly believes PayPal should stay part of the company.
EBay Inc. said Monday its four directors up for reelection—CEO John Donahoe, company co-founder and managing director Fred Anderson, Intuit co-founder Scott Cook, and former Agilent Technologies CEO Edward Barnholt—should be supported by shareholders.
Icahn has put forth two candidates for the board who are his employees and has urged shareholders to vote against eBay's directors.
In an online post Monday, Icahn reiterated that he believes PayPal should be spun off, the directors up for reelection should resign, and his candidates for the board should be voted in.
He has complained that Donahoe has not acted in the best interest of shareholders. For example, he said he believes eBay sold video-chat site Skype prematurely and cost shareholders $4 billion.
EBay responded in support of its CEO, saying that the company's stock price has more than quadrupled since Donahoe took the helm in 2008. It said Icahn is acting in pursuit of his own "profit motives."
Shares of eBay, which is based in San Jose, Calif., fell 75 cents, or 1.3 percent, to $58.41 in afternoon trading. The stock is up about 6 percent so far this year.