Time Warner’s AOL announced today it will acquire ad firm TACODA for an undisclosed sum. But according to sources familiar with the deal the company paid $275 million for TACODA.

TACODA, a company founded in 2001, offers a technology that enables advertisers to serve highly relevant ads based on consumers’ online behaviors,

The behavioral targeting market is set increase to $3.8 billion by 2011, according to analysts.

TACODA employs approximately 100 people and AOL said the company will operate as a wholly owned subsidiary.

“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,” said Ron Grant, AOL President and COO.

“We are committed to bringing advertisers and publishers a full range of tools and services, along with the widest reach, and with TACODA we’re taking another step toward that goal.”, he added

Also AOL recently purchased German network AdTech AG and Third Screen Media, a mobile advertising network, which will live within its Advertising.com unit, which was bought in 2004.

Last year, AOL acquired Lightningcast, a company that delivers advertising solutions for on-demand, live and downloaded video content across the Web.