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Are AOL and Yahoo really thinking again about merging?

Anyone getting excited about fresh talk of an AOL merger with Yahoo should take a deep breath.

New chatter on the topic started early Wednesday after the publication of a New York Times Magazine article by Business Insider reporter Nicholas Carlson, who published an adaptation from his largely historical book, "Marissa Mayer and the Fight to Save Yahoo!"

Tim Armstrong
Jason Alden | Bloomberg | Getty Images

A quote from another excerpt in Business Insider teased the possibility that AOL CEO Tim Armstrong might be open to a deal again.

"Major Yahoo shareholders have recently begun collaborating on a series of spreadsheets that calculate that AOL and Yahoo are worth between 70 and 80 percent more when combined than they are apart," said the excerpt.

The story goes on to say that Armstrong has seen "a version of this spreadsheet and that he would be willing to consider a deal."

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Let's back up a second. While a merger between AOL and Yahoo has been suggested by observers for years, it's unlikely to be front of mind for either company. The most recent time Armstrong spoke up about it in October, he said he wasn't thinking about a deal.

As for Yahoo CEO Marissa Mayer, she has made clear the company is focused on a tax-efficient divestiture of its stake in China'a Alibaba Group, which accounts for the vast majority of Yahoo's value. (Yahoo is worth $46 billion while AOL is worth a mere $3.3 billion). AOL didn't respond to a request for comment while Yahoo declined to comment.

Has anything changed since then? There's little reason to think so.

Several large Yahoo investors interviewed by CNBC on Wednesday said the focus remains on how the company can divest the Alibaba stake. As outlined in a CNBC story last month, Yahoo shareholders reiterated that it would be a mistake to focus too much on an AOL merger. The tax savings from an efficient sale of Yahoo are worth about $16 billion based on Wednesday's share price. A merger with AOL could generate about $6 billion, based on assumptions laid out in the story.

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Carlson suggests that some Yahoo shareholders have shown Armstrong "spreadsheets" outlining the value of a merger with Yahoo.

According to a person familiar with the matter, Armstrong has routinely discussed Yahoo with shareholders, particularly in the last few months after Starboard Value suggested AOL merge with Yahoo's core business. But Carlson gives no reason explaining why the merger is a better deal than it's ever been. Carlson's "spreadsheets" assume merger synergies of $1 billion, the same figure assumed in previous CNBC stories.

Of course, a merger between the two companies can never be ruled out, especially after Yahoo follows through with its divestment plans.

But maybe the real reason for the buzz is simpler: The old-fashioned promotion of a book.