A Texan oil billionaire has sold all of his shares in Yahoo in protest at how the company has handled Microsoft's various bids to buy its search business.

Billionaire investor Thomas Boone Pickens spent millions of dollars buying up 10 million shares in Yahoo earlier on in the year.

However, Pickens has now sold his entire stake and has put the boot in too, criticising Yahoo's management as "pathetic".

In particular, he says that he is sick of waiting for Yahoo to accept a deal with Microsoft - something which is now looking increasingly unlikely.

"I think that Yahoo management was pathetic", Pickens told The San Francisco Chronicle.

Microsoft has now made a statement saying that it is going to pursue other projects after Yahoo rejected its second takeover bid.

Another unhappy shareholder, Carl Icahn, seems to have settled his problems with the web company, and has accepted three seats on Yahoo's board.