This story has been updated with Microsoft’s and Yahoo’s response.
The ongoing saga of the Yahoo sale could now involve the potential entry of Microsoft and its largesse of cash.
While it would seem Microsoft (msft) has no intention of making a more significant, direct bid—the company publicly tried and failed to acquire Yahoo back in 2008—the software giant appears to be influencing the potential winning acquisition of Yahoo’s core business. Microsoft already has search and advertising ties with Yahoo, with a 10-year search deal signed in 2009 that at one point made up 31% of Yahoo’s revenues.
The terms of that search deal were recently renegotiated under CEO Marissa Mayer, and the latest inclusion of Microsoft indicates it wants to protect its invested relationship—and also has the means to do so.
“If Microsoft put in a billion, it would cost them almost nothing,” one investor who had spoken to Microsoft told Recode. “It’s a minor thing and it buys them a lot.”
Add Microsoft to the list of big names potentially attached to a Yahoo acquisition, including Verizon (vz), Fortune‘s publisher Time Inc. (time), and a host of private equity firms including KKR (kkr) and Vista Equity Partners.
The price tag for Yahoo’s core business—which would factor in its digital business and advertising platforms—is estimated to be around $6 to $8 billion, although sources told Recode Yahoo was seeking $10 billion.
Potential bidders will need to sift through Yahoo’s passive-aggressive strategy, and the apparent reluctance of Mayer to sell Yahoo’s core business in the first place. A letter from activist hedge fund Starboard Value on Thursday called for the entire Yahoo board to be replaced, saying that Yahoo’s pace in talks “cast doubts for prospective buyers of the core business as to whether the process is genuine and whether they should commit the time and resources to evaluating a bid and making a proposal.”
A Microsoft spokesperson told Fortune the company had no comment at this time. Yahoo reiterated the same. “We have no comment on the reports,” a Yahoo spokesperson told Fortune.