Michael Dell (News - Alert) may have a computer company named after him, but that doesn’t mean his attempt to make the company private will go unopposed.

Southeastern Asset Management, which was identified by The Associated Press (News - Alert) as Dell's largest independent shareholder, as well as investor Carl Icahn, are challenging Michael Dell's $24.4 billion effort to make the company private. Together, Ichan and Southeastern hold 13 percent of the company's stock, according to The Wall Street Journal.

Southeastern and Icahn want shareholders to be able to keep their stock in the company, and pay them another $12 a share or other shares. On the other hand, Michael Dell wants to pay $13.65 a share.

"We want this board to hear from both Icahn and Southeastern loud and clear that it is insulting to shareholders' intelligence for the Board to tell them that this board only has the best interests of shareholders at heart, and then accept Michael Dell's offer to purchase the company he founded for $13.65 per share, a price far below what we consider its value to be," a May 9 letter from Icahn and Southeastern said, TMCnet reported.

Members of a board committee are currently reviewing the proposal from Icahn and Southeastern.

Under his plan, Michael Dell and Silver Lake Partners want to buy out company shareholders for $13.65 a share. He and some of his supporters control about 16 percent of Dell's stock, The Journal said.

The opponents are unhappy with the plan and with the board.

"You now have the opportunity to ameliorate the damage that we believe you have caused to Dell and its shareholders by following the fair and reasonable path set forth in this letter," the Southeastern and Icahn letter adds. “We are often cynical about corporate boards, but this board has brought that cynicism to new heights… This company has suffered long enough from very wrongheaded decisions made by the board and its management.”

Icahn and Southeastern plan to nominate a slate of new directors at an upcoming annual meeting, Forbes said.

“In the event that the Board does not find our offer to be ‘superior’ and insists on presenting the Dell offer for a shareholder vote, we will work assiduously to persuade all shareholders to reject the Dell offer,” the letter warns.