Fiorina tended her resignation on February 9, following a tumultuous five-and-a-half-year run at HP. She tried but failed to buy the IT unit of PricewaterhouseCoopers (now part of IBM), and succeeding in acquiring Compaq after a bitter shareholder battle that pitted her against the Hewlett and Packard families. The Compaq merger has been widely criticised.

Fiorina’s departure follows differences between herself and the HP board on HP’s strategy, and analysts now predict that the company could eventually be broken up.

Merrill Lynch, which upgraded the stock on the news, said in a research note: We believe the long-term probability of a breakup of the company is rising, despite indications from the board that no such move is currently planned.