A Key Figure in the Future of Yahoo

“I shouldn’t make a comment on that,” said Masayoshi Son, the usually voluble serial entrepreneur who is one of the richest men in Japan. “It’s too delicate a question. Too sensitive right now.”

We had been chatting for some time on the 26th floor of the headquarters of his company, Softbank, seated in a conference room that offered sweeping views of Tokyo Bay. What had caused Mr. Son to turn cagey all of a sudden?

I had mentioned Yahoo.

If there is one person who holds the key to the future of the American Internet also-ran, it may be Mr. Son, the 53-year-old billionaire founder of Softbank.

While Mr. Son is little known in the United States, Softbank owns big chunks of Yahoo’s most valuable investment stakes: Yahoo Japan and the Alibaba Group, one of China’s largest Internet companies. Combined, analysts estimate, those assets, along with Yahoo’s cash, represent more than half of Yahoo’s $22 billion value.

With all the speculation about Yahoo’s future — Will it be broken up? Will it be taken private? Will it merge with AOL? — virtually every situation contemplated begins and ends with Yahoo selling its Asian crown jewels. And that is where Mr. Son comes in, perhaps on either side of a deal. (By the way, the chance of AOL buying Yahoo is next to never.)

Indeed, Mr. Son has held back-channel discussions with Yahoo, as its chief executive, Carol A. Bartz, plans the company’s future, people involved in the talks said. Mr. Son declined to comment, saying only, “She has to make a hard decision.”

No deal is imminent — and one may never come — but the betting line is that Ms. Bartz has no more than a year before she must shake up Yahoo or lose her job. A person close to the board said she had its full support through at least the end of her contract, which runs through 2012.

A Yahoo spokesman said, “Our Asian assets and our Asian relationships are very valuable to Yahoo.”

Still, Mr. Son, who most recently brought Apple’s iPhone to Japan, is clearly depressed about the state of the company. In 1996, he started Yahoo Japan as a joint venture with Yahoo; now he is its controlling shareholder.

In the last decade, Yahoo Japan held onto its dominant spot here while Yahoo languished virtually everywhere else. Just this month, in what may be the ultimate symbol of Yahoo’s fall, Mr. Son had Yahoo Japan begin using Google as its search engine on its home page.

“Yahoo was Jerry Yang’s baby. He did a great job creating the baby,” he said. “Unfortunately, some of the key executives after the foundation of the company couldn’t keep up with the technology innovation of the industry. They thought that Yahoo should become a media company.”

As he spoke, he got more and more agitated: “I said from the very beginning, ‘Yahoo should position itself as a technology innovation company, not as a media company.’ ”

Mr. Son is particularly frustrated with the way Yahoo approached international markets. While he persuaded Yahoo to allow him to create a stand-alone site in Japan, Yahoo chose to run its own operations in most other parts of the globe.

“You need a local hero,” he said, suggesting that Yahoo was too arrogant with its global approach, especially around media. He said its expansion strategy was the equivalent of saying, “You’re the only smart guy and those slaves in the poor counties are dumb guys.”

He added, “If they had listened to me and had equal partnerships in China, the U.K., Germany and Brazil, maybe Yahoo in those countries could have become positioned like Yahoo Japan.”

Of course, Mr. Son has had his own ups and downs. He started Softbank in 1981 as a publisher of software and media. By the late 1990s, Softbank, which was making itself into an Internet company, was worth as much as $180 billion. Today it is worth only $20 billion. Mr. Son is said to have lost nearly $70 billion personally.

But his stakes in Yahoo Japan and in Alibaba (he is also a board member) — along with the acquisition of Vodafone’s Japanese business in 2006 — have kept him as one of the most influential investors in Asia.

Over the last year, Alibaba has sought to buy back Yahoo’s stakes in the company, but to no avail. Yahoo owns 40 percent of Alibaba and 35 percent of Yahoo Japan.

Ms. Bartz has been holding off from trying to sell Yahoo’s investments in Asia — especially Alibaba — because, it is said, she and others on the board think there will be more value when some of Alibaba’s most profitable parts, Taobao and Alipay, go public.

“It would be difficult for Yahoo to get fair market value on these assets given the environment in which they would be divesting,” Gene Munster, an analyst with Piper Jaffray, wrote when speculation surfaced that Yahoo might seek a deal.

Still, if Yahoo were to sell those stakes, it would create a big cash pile, which the company could use to take itself private or make some significant acquisitions.

“With Yahoo Japan outsourcing search to Google, Yahoo has several assets that do not have a lot of synergies, and we think the sum of the parts is worth more than the whole,” Justin Post, an analyst with Bank of America Merrill Lynch, wrote.

So what would Mr. Son do if he were running Yahoo?

“If I were Yahoo’s U.S. C.E.O., I would have my own view and own approach. But my approach is always riskier. I always take bold moves. So it can have great return but with great risk,” he said. “I would be more aggressive to acquire companies or start a new business.”

With a laugh, he added that shareholders of Softbank might have more tolerance for risk than Yahoo’s shareholders. Softbank’s shares, he said, “go sky-high and to hell all the time. Our shareholders in Japan are used to it.”

And then, having discussed more about Yahoo than he might have wanted to, he hinted ever so slightly that he expected a deal to be made eventually.

“Our interests and her interests do not necessarily contradict each other,” he said. “Sooner or later we will have a win-win situation.”