Twitter buys a company backed by...Twitter's CEO

Twitter works to improve ad targeting
Twitter works to improve ad targeting   

Twitter just announced that it acquired an online advertising company called TellApart. Among its investors: the guy who runs Twitter.

Dick Costolo, Twitter's CEO, invested in TellApart in 2010, as part of a $4.8 million round that included Greylock Partners, LinkedIn founder Reid Hoffman and SV Angel.

Alongside the microblogging site's first-quarter earnings announcement on Tuesday, Twitter said acquiring the personalization technology gives it "additional tools for cross-device identity, targeting and attribution, along with a talented team with deep direct response expertise."

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TellApart was founded in 2009 by Josh McFarland, a former Google executive, and raised an additional $13 million in 2011 in a financing round led by Bain Capital Ventures.

It's a fiercely competitive market that includes publicly-traded Criteo, as well as start-ups like AdRoll and SteelHouse. Ad tech has been a tough place for independent companies to scale, and Twitter has proven to be a willing acquirer after purchasing MoPub in 2013.

"Together, we're excited to bring the power of cross-device targeted advertising to Twitter, our clients and our ad exchange partners," McFarland said, in the statement.