Tacoda is based in New York and will operate as a wholly-owned subsidiary of AOL. It allows advertisers to target consumers by studying their online behaviour.
Using Tacoda's technology, AOL will be able to extend the reach of its third-party display network.
Ron Grant, AOL President and chief operating officer, said: "The acquisition of Tacoda will build on our advertising momentum, letting us better serve advertisers by enhancing our ability to precisely target advertisements across an even broader network."
Curt Viebranz, CEO of Tacoda, said: "AOL is a perfect match for Tacoda. By combining our targeting capabilities with AOL's existing set of solutions, we can better serve online advertisers and publishers as the market for behavioural targeting continues to emerge."
Other recent acquisitions by AOL this year include Third Screen Media, the mobile advertising network and software provider, and AdTech AG, the online ad-serving company based in Frankfurt, Germany.