But that doesnt mean that it wont happen, and that is exactly what the latest industry rumors claim.
So far, there isnt much solid evidence that the two companies are talking. Investors have been snapping up call options for Yahoo stock, which means they are betting that Yahoo stock is going to rise during the next month.
It could be because rumors are percolating that Microsoft want to at least buy a piece of Yahoo or perhaps buy the entire company.
But investors could also be buying options just because they expect Yahoo to report strong quarterly sales and earnings this month.
The Los Angeles Times on Jan. 1 went as far as to write that the flurry of speculation was because Yahoo had already refused a Microsoft buyout offer of $80 billion because it was too low.
Neither company will comment. But if Microsoft had a formal unsolicited offer, Yahoos board would have had to make a formal reply, and government regulators as well the media would have gotten the word.
Its more likely that that Microsoft has put out unofficial feelers to find out whether Yahoo would be amenable to a friendly partnership or merger.
In that case, the two companies wouldnt be obligated to disclose their talks unless they reached an agreement.
The working theory is that Microsoft is still determined to acquire at least a piece of a major Internet portal company, since Google outbid Microsoft to acquire a 5 percent share of America Online.
Buying Yahoo would provide a quick way for Microsoft to increase its share of the rich Internet advertising market rather than to keep building up the audience share and advertising revenue of its MSN Web portal.
Microsoft and Yahoo already have a relationship in place. In October, the two companies agreed to link their instant message systems to create what they say is the worlds largest IM community.
That Microsoft might be willing to pay billions buy rather than build up its Web presence is more evidence of the maturation of the technology industry.
Microsoft cant expect that it can sustain double-digit revenue growth based on the sale of operating systems and applications alone.
It is a sign that Microsoft is prepared to become more of a media company and less of a technology company because that is where the growth and the competition are.
Microsoft faces the challenge of either buying a Yahoo or conceding dominance of the Web advertising-search market to Google, and that is a condition its constitutionally unable to accept.
It doesnt appear likely after years of trying that MSN will overtake Google or Yahoo as the top search portal on the Internet through organic growth.