Michael Dell’s takeover offer for the company he created is coming under attack from shareholders, activist investor Carl Icahn, and even two PC maker rivals. Each seeks to undermine or at least raise the stakes of the $24.4 billion deal, clouding the future of the company.

Mr. Dell announced the deal to take his firm private in February, revealing at the time that he was working with investment firm Silver Lake, four banks, and Microsoft to raise the $24.4 billion needed to pay stockholders $13.65 for each share of Dell common stock they hold. But there have been shareholder complaints since the announcement, most centered on the value of the company, and many coming from large institutional investors. And many are seeking more than $13.65 per share.

This week, the efforts to scuttle or at least raise the price of the deal have intensified.

Controversial activist investor Carl Icahn revealed that he has quietly purchased 6 percent of Dell’s stock in recent weeks and is pushing the firm to undergo a leveraged recapitalization instead of allowing Mr. Dell to purchase the company. He wants Dell to borrow billions of dollars to pay shareholders $15.7 billion in a special dividend, and then remain a publicly-held company.

But the Special Committee of Dell’s Board of Directors, which is overseeing the transition, says that it considered recapitalization, along with changing its dividend policy and even breaking up the company, and determined that the sale to Mr. Dell would be the best for shareholders.

“We negotiated aggressively to ensure that stockholders received the best possible value and agreed to a $13.65 per share transaction that provides value certainty at a 37 percent premium above the average price for the 90 days before rumors regarding the transaction surfaced,” a statement from the Special Committee notes. “The Special Committee has worked hard, and continues to work hard, to produce the best outcome for Dell’s shareholders.”

Meanwhile, HP and Lenovo, currently the number one and two PC makers ahead of Dell, are working to undermine the deal as well. Both have “expressed interest” in the company in a transparent bid to drive Dell’s stock price up and increase the buyout price. (Lenovo says it was approached by outsiders concerning a bid but wasn’t interested.)

Put simply, it seems that the $13.65 price point for Dell’s shares is going to have to go up in order for this deal to conclude. But given the difficulties Mr. Dell had in raising the $24.4 billion for the original offer, it is unclear where any additional money could come from.