Will Microsoft buy not all of Yahoo but only its search business? Can Yahoo stave off corporate raider Carl Icahn? Might Google yet team up with Yahoo?

In an effort to buy itself time to head off shareholder activist Carl Icahn's mission to nominate a slate of completely new directors for the search giant, Yahoo has made an SEC filing saying that its July 3 AGM is postponed till the end of July. One of its current ten directors, Edward Kozel, also resigned from the board and will not be replaced.

The regulatory filing comes as Microsoft continues its quest to negotiate a partial alliance with Yahoo to replace its previous all-out acquisition strategy.

Carl Icahn, meanwhile, told an audience in New York last night, that Microsoft should definitely step in:

"Microsoft would be crazy to give up this opportunity that we handed them in this fight...These companies should be merged in one way or another."

Yahoo's stock is up 18% so far this year and is attempting to come up with a deal with rival Google whereby Google would sell ads appearing alongside Yahoo's search results. In an alternative strategy Microsoft is rumored to be bidding now for Yahoo's search business only (worth $21BN according to Sandeep Aggarwal, an analyst quotes by the Financial Times) - leaving out of the transaction its display and communications properties (worth $1BN) and its investments in Asian partners ($9.25BN).

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