Activist investor Carl Icahn escalated his attack on eBay Inc. Chief Executive Officer John Donahoe and the company’s board, calling its governance “dysfunctional” and riddled with conflicts.

Icahn, the billionaire who last month proposed that eBay spin off its PayPal unit, sent his second letter to shareholders in three days, highlighting the competing interests of directors Marc Andreessen and Scott Cook. In its response to the Feb. 24 letter, eBay said Icahn was “mudslinging.”

“There is no question that they are accomplished and value-driven, but we believe the primary problem, among other things, is that they appear to be value-driven for themselves,” Icahn wrote, reiterating his call for investors to vote for two new directors and support a separation of eBay and PayPal. “Let’s end this charade.”

Icahn, 78, says that Andreessen, a venture capitalist, unduly profited from eBay’s sale of videoconferencing-company Skype while he was on the board by participating in the acquisition of the unit and then selling it to Microsoft Corp. at a much higher price. Cook is a director at Intuit Inc., a company Icahn said is a “fierce” eBay competitor.

EBay, based in San Jose, California, rose 1.7 percent to $57.08 at 10:41 a.m. in New York. The shares had gained 2.3 percent this year through Wednesday.