Marc Benioff tried to buy LinkedIn even after it announced the deal with Microsoft

After LinkedIn officially announced that it had sold itself to Microsoft for $26.2 billion in cash last month, Salesforce CEO Marc Benioff, a rival bidder, didn't give up right away.

Instead he sent an email to cofounder and chairman Reid Hoffman and CEO Jeff Weiner that essentially said he would have been willing to pay much more for LinkedIn, had he been given the chance, according to documents filed with the SEC on Friday.

Salesforce was one of three other companies besides Microsoft who were also bidding on LinkedIn. Numerous media reports named Salesforce as the infamous "Party A," the one who engaged in bidding war with Microsoft, as revealed by LinkedIn in SEC documents that explaineddetails of how the deal went down.

Salesforce's last offer before LinkedIn chose Microsoft was $85 in cash plus stock that equaled $200 per share. Ultimately, Microsoft offered $196 cash per share and the two companies announced the deal on June 13.

An email to reconsider

In an SEC filing on July 1, LinkedIn disclosed to the world how the bidding war went down.

That disclosure prompted Benioff to email Hoffman and Weiner to say that if LinkedIn would have communicated to him that his previous offer wasn't good enough, Salesforce (aka "Party A") would have offered "much" more.

"The email indicated that Party A would have bid much higher and made changes to the stock/cash components of its offers, but it was acting without communications from LinkedIn," LinkedIn explained in SEC documents. The document does not specifically name Benioff as having authored the email, but says that it was written by the CEO of Party A.

It was a not-so-subtle play to get LinkedIn to reconsider its commitment to Microsoft. And on July 7, LinkedIn met with its bankers to discuss Benioff's email, LinkedIn said, but ultimately decided not to respond.

One reason: Although LinkedIn has the option to bail on the agreement and take a better offer, if it does that, it will owe Microsoft "a termination fee of $725 million."

Benioff wanted LinkedIn for the same reason Microsoft does. Both of these companies see LinkedIn's massive network of more than 433 million professionals as data that can be mined with machine learning artificial intelligence and then used with their sales, marketing and collaboration software.