SUNNYVALE, California: Yahoo investors are up in arms following Microsoft's withdrawal of its $47.5 billion (€30.7bn; £24bn) offer for the troubled web search pioneer.

Co-founder and ceo Jerry Yang (pictured) will now face intense scrutiny over his management of the company after his refusal to accept the sweetened deal, and the software giant's surprise decision to walk away rather than renegotiate.

Dissident shareholder Eric Jackson has already said he will urge fellow investors to withhold votes for all of Yahoo's directors at its annual meeting.

Thunders Jackson: "Significant value was left on the table."

Yang, however, has defended his position saying the unsolicited bid from Microsoft was a distraction.

He says the offer greatly undervalued Yahoo and the company could do just as well if it continues to go it alone.

He adds: "We will be able to focus all of our energies on executing the most important transition in our history so that we can maximize our potential to the benefit of our shareholders, employees, partners and users."

Microsoft, seeking the acquisition of Yahoo to strengthen its challenge to Google's dominance of web search and online advertising, will now have to chart a different course - which as yet remains unclear.

Nonetheless, ceo Steve Ballmer told the company's employees: "Although the acquisition of Yahoo would have accelerated our ability to deliver on our strategy in advertising and online services, I remain confident that we can achieve our goals without Yahoo."

Data sourced from BBC Online; additional content by WARC staff