Dell Inc announced today that proxy investment advisory firm ISS recommended the US$24.4 billion offer by chief executive officer Michael Dell for the company, according to the PC maker's special committee.

The chief executive is financed by the equity buyout firm Silver Lake. He also ruled out a US$13.65 per share raise on the offer, said sources familiar with the pending transaction last week.

Michael Dell's offer was previously challenged by a counter bid made by Carl Icahn and Southeastern Asset Management. Icahn, an American business magnate and billionaire, offered a rival bid which will reflect into a total of over 1 billion shares priced at US$14 per share.

The computer manufacturer's shares shot up to 2.3% in premarket trading today. Dell closed at $13.30 last Friday on the Nasdaq.

The ISS, or Institutional Shareholder Services, is the biggest proxy advisory firm in the world.

Michael Dell currently owns a 16% stake in the company.