By MICHAEL LIEDTKESAN FRANCISCO (AP) â¿¿ Dell's largest independent shareholder is leaning toward supporting one of the two bidders trying to scuttle the slumping personal computer maker's proposed $24.4 billion sale to a group including CEO Michael Dell. Southeastern Asset Management expressed its preliminary support for the alternative offers in a letter sent Tuesday to the four-person committee overseeing the negotiations. The development doesn't come as surprise, given that Southeastern has been the most vocal opponent to Dell Inc.'s plan to sell itself to Michael Dell and Silver Lake Partners for $13.65 per share. That price struck Southeastern as too low. The Memphis, Tenn., investment firm tried to prove its thesis Tuesday by noting that Dell Inc. has spent $3.4 billion during the past two years buying back the company's stock at an average price of $15.25 per share. "The same board that was confident with Dell buying its shares for $15.25 is now attempting to convince all shareholders that Dell's business is in such dire straits that they should take $13.65 and exit their investments," Southeastern's top executives, O. Mason Hawkins and G. Stanley Cates, wrote in the letter. "We believe the Board's sudden rush to sell is triggered by one thing: Mr. Dell's desire to buy. The backlash to the board's deal with Michael Dell emboldened buyout specialist Blackstone Group and billionaire investor Carl Icahn to submit separate proposals offering a slightly higher price. Blackstone is proposing to buy most of Dell Inc.'s stock for $14.25 per share while Icahn is willing to pay $15 per share for up to 58 percent of the shares. Dell's stock dipped a penny Tuesday to close at $14.19. Unlike the deal with Michael Dell, a portion of the company's stock will remain publicly traded if Blackstone or Icahn prevail. That would allow current shareholders such as Southeastern to share in some of the future gains if Dell Inc. successfully executes on a plan calling for the company to lessen its dependence on the shrinking PC market and diversify into more profitable sectors such as selling data storage services and business software.