They should start selling tickets for those Yahoo! board meetings.

Carl Icahn yesterday talked about working in partnership with the internet search company as it announced that the veteran activist investor would be joining the board.

But after the highly personal attacks exchanged between Mr Icahn and Jerry Yang, the company’s chief executive, the partnership will be a strained one. Mr Icahn has portrayed Mr Yang as a geek who doesn’t know how to run a business; Mr Yang has painted Mr Icahn as a dinosaur corporate raider who doesn’t know how to use a computer. (Both caricatures may have some truth in them.)

Mr Icahn said yesterday that he was keen to develop “a strong working relationship” with the company’s management to help it to achieve its full potential.

What he meant was that he was keen to find some way to achieve the full potential of his investment in Yahoo!, on which he is currently nursing a big loss.

Mr Icahn quietly bought around 55 million shares during the first two weeks of May, which represented a 4 per cent holding, when the Yahoo! share price was as much as 24 per cent higher than it is now.

While it is not known what price he paid for the 14 million shares acquired since then, his paper losses are estimated at almost $400 million.

It will be Mr Icahn’s attempt to recoup these losses that will keep the pressure on Yahoo! to complete a partial or full sale to either Microsoft or another company, such as Time Warner.

Yahoo! turned down another approach from Microsoft last week after failing to agree a takeover at a 62 per cent premium earlier this year.

In frustration, Mr Icahn had proposed replacing Yahoo!’s entire board at the company’s shareholder meeting on August 1.

But investor support for his campaign appeared to be waning, with Bill Miller, the veteran Legg Mason fund manager, last week declaring that he would not back Mr Icahn.

So Mr Icahn agreed to abandon his fight in return for a board seat and the right to propose two other directors.

Some observers have expressed surprise that Yahoo! has offered any compromise to Mr Icahn, given his hostility to the board’s position.

Mr Icahn’s public attitude towards Yahoo! may have been toned down now that he has been invited to attend the monthly meetings in San Jose. But his intentions have not.

He has shown little confidence in Mr Yang’s belief that the company can grow on its own in a market increasingly dominated by Google. Or, indeed, that it can on its own boost its share price from the present $21.67 to the $33 a share that Microsoft offered to pay in May.

Although he will control only three seats on Yahoo!’s expanded 11-strong board, his presence must increase the chances of an eventual sale of all or parts of the company to Microsoft.

One of the directors proposed by Mr Icahn is Jonathan Miller, former head of the rival internet service AOL. Analysts say that Mr Icahn could bring in Mr Miller to run the company if Mr Yang fails to deliver on his promises.

Or maybe Mr Icahn thinks that Mr Miller could help to engineer another deal – combining Yahoo! with AOL. That would help Mr Icahn to achieve a previous ambition. It would involve the demerger of AOL from Time Warner, a separation that Mr Icahn tried and failed to force two years ago.

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