Salesforce is considering buying messaging app Slack: WSJ

Salesforce held talks to buy the workplace messaging app Slack, The Wall Street Journal reported on Wednesday.

The WSJ later updated the story to say Salesforce is in advanced talks with Slack, and that a deal could be announced within days, potentially by the time Salesforce reports its quarterly earnings on Tuesday.

There is no guarantee that the talks will lead to an acquisition, the report said, but a deal would signal a more aggressive foray into office communication for the cloud giant. Salesforce has two communication and collaboration tools, Chatter and Quip, which can be used in tandem with its customer-management-focused tools.

The move would represent Salesforce's largest acquisition in its history, as Slack's market capitalization was at about $17 billion before the report and the acquisition price would likely be higher. Slack's stock surged as much as 32% on the news, while Salesforce shares were down about 3.5%. Neither company was immediately available for comment.

This would also continue Salesforce's acquisition spree of late. The customer-management-software provider has made two large acquisitions in the past few years: It bought the data-visualization company Tableau for over $15 billion in 2019 and MuleSoft for $6.5 billion in 2018.

CEO Marc Benioff notably said on the company's quarterly earnings call in August that he didn't "really see an M&A environment" for large companies like his at this time. He also said Salesforce was focused on integrating its MuleSoft and Tableau acquisitions this year.

But Salesforce has made a few smaller acquisitions so far in 2020, buying Vlocity for $1.3 billion in February and The CMO Club, a marketing network, for an undisclosed amount in early March.

Analysts have recently speculated that Salesforce might need to rely on acquisitions to keep up its rapid pace of growth; a UBS analyst note said the firm was suffering from a "lack of innovation."

Salesforce and Slack have had a partnership since 2016 and expanded it last year so users could move more seamlessly between both cloud services.

Both companies compete with Microsoft: Salesforce with Microsoft's customer-relationship-management tools, and Slack with Microsoft Teams, its chat and collaboration app. A merger could position both companies as a stronger competitor to Microsoft.