Oracle Corp., the world’s largest maker of database software, is buying Involver Inc., the third acquisition in two months aimed at helping customers use social-media tools to market wares and run their businesses.

Closely held Involver makes software tools that let companies interact with customers on Facebook Inc. and Twitter Inc.’s social-networking services. Its products also let marketers create customized Facebook pages to represent their brands. Terms of the deal weren’t disclosed.

Chief Executive Officer Larry Ellison is using dealmaking to step up rivalry with Microsoft Corp. and Inc. in the market for social-media software. Oracle said in May that it’s buying Vitrue Inc., which helps companies run marketing campaigns on Facebook and Twitter. It announced plans the following month to buy Collective Intellect Inc., which analyzes customer data culled from websites.

“Companies are looking to harness the full potential of social media to increase brand loyalty, connect with potential customers and anticipate buyers’ needs,” Redwood City, California-based Oracle said on its website. “The combination of Involver with Oracle is expected to create the most advanced and comprehensive cloud-based social platform across marketing, sales and service touchpoints.”

Salesforce said on June 4 that it would pay $689 million for Buddy Media Inc., which helps companies create social media campaigns.

Weeks later, Microsoft said it agreed to pay $1.2 billion for Yammer Inc., maker of software that lets employees collaborate in the workplace.

Customers of Involver include Best Buy Co. Inc., Toys “R” Us Inc. and Viacom Inc.’s MTV Networks, according to Involver’s website.

The market for social-media management tools will more than double to $970 million in 2016, from $389 million this year, according to Forrester Research Inc. This category includes Facebook page managers such as Buddy Media, as well as so-called “listening platforms,” which let businesses monitor conversations about their brands on social networks.