News Corp. Chairman Rupert Murdoch plans to forgo making deals at this year’s Allen & Co. media retreat, dampening the five-day event renowned as an incubator for big-time media and Web combinations.

“Not today, not this week,” Murdoch told reporters Wednesday morning on his way to the annual retreat’s opening breakfast. Murdoch built his media and entertainment empire through brash dealmaking at Sun Valley and elsewhere, including last year’s purchase of Dow Jones Co., publisher of the Wall Street Journal.

Murdoch’s presence signifies the importance of the Allen event, but his certainty that no deals are afoot underscores the uneasy times facing many media and Web moguls.

Many of them arrived this year at the closed event with their stock prices at multiyear lows as investors increasingly question how media companies are addressing the loss of advertising revenue to the Web and as Internet firms try to maximize their investments.

Much of the talk at the retreat so far has centered on speculation over the next move in the complex takeover dance between faltering Internet pioneer Yahoo Inc. and its unbidden suitor, Microsoft Corp.

Yahoo CEO Jerry Yang, who rejected a $33-per-share bid from the world’s largest software maker in May, saying the company he helped found is worth $37 per share, isn’t expected to arrive until Thursday. And billionaire investor Carl Icahn, who owns about 4 percent of Yahoo and has been agitating for a sale, isn’t expected at all. Icahn reportedly bought his stake for $25 per share.

Microsoft Corp. dealmaker Henry Vigil, head of strategy and development, looked overwhelmed as photographers circled him when he arrived Tuesday. He did not answer questions from reporters.

Microsoft co-founder Bill Gates is expected Friday.

Bill Miller, whose Legg Mason Capital Management Inc. owns just over 5 percent of Yahoo, said Icahn, who is trying to unseat Yang by taking over Yahoo’s board at its Aug. 1 annual meeting, would get more support if he promised to hold out for $33 per share.

Gordon Crawford, who runs Yahoo’s largest shareholder, Capital Research Global Investors, did not speak to reporters on the record. He is expected to seek out Vigil and Gates during the retreat.

The 26th annual conference kicked off Wednesday with a morning of closed-door presentations, starting with Jeff Bezos, the founder of Amazon.com.

In recent years, cheap credit sparked a flurry of deals on Wall Street, but the credit crisis, swooning stock market and flagging economy have slowed that, and this year’s retreat is notable for a lack of private equity investors.

Henry Kravis, of Kohlberg Kravis Roberts & Co., is the highest-profile money man on the guest list. Mario Gabelli, chairman of Gamco Investors Inc. in New York, is also here, but he’s been tightlipped on the prospects for investments.

That leaves the barons with plenty of time to focus on the future of their own businesses, which are in various states of disarray. Some food for thought came in the form of writer Ken Auletta’s talk “Looking Around the Corner to the Future” Wednesday morning with Marc Andreessen, a co-founder most recently of social-networking site Ning.

Time Warner Inc. CEO Jeff Bewkes, Viacom Inc. boss Philippe Dauman and other bosses of old-line companies will want to keep an eye on Internet startups as they try to recoup lost ad revenue that has shifted online.

That makes the likes of LinkedIn’s Reid Hoffman, fresh off an investment that valued his company at $1 billion, popular participants. He rolled up Tuesday in a convertible Chrysler Sebring, in stark contrast to the austere SUVs with tinted windows that delivered many of the barons to this famed resort.