NEW YORK – IBM Corp. (NYSE: IBM) said Friday it has agreed to buy Unica Corp. (Nasdaq: UNCA), a marketing services company, for $480 million, or $21 per share.

The acquisition brings IBM deeper into the advertising business, a relatively new area for the company. In June the Armonk, N.Y., company agreed to buy Coremetrics Inc., a company that helps target online marketing.

It also expands IBM’s software business, its most profitable division and the main focus of a $20 billion acquisition spree for IBM over the past few years.

Unica, based in Waltham, Mass., offers software that automates the process of predicting customer preferences, designing advertising campaigns based on that information and measuring how effective they are.

"IBM understands the demands on today’s organizations to transform core business processes in functions such as marketing with intelligence and automation," said Craig Hayman, general manager of IBM Industry Solutions. "Unica was a clear choice for IBM based on its power to automate a broad set of marketing capabilities and its established reputation for delivering customer success in marketing to organizations around the world."

The rise of the Web as an advertising platform has heightened demand for marketing that has a measurable impact. And IBM wants to provide the tools for doing that kind of targeting, Craig Hayman, IBM’s general manager for Industry Solutions, said in an interview. "Unica brings science to the search for better outcomes," Hayman said.

Unica generates annual revenue of more than $100 million and has more than 1,500 clients, including Best Buy Co. and eBay Inc. In the previous fiscal year, which ended September 2009, it booked a net loss of nearly $22 million but has since posted three profitable quarters in a row as businesses restore marketing budgets coming out of the recession.

"Unica’s focus is to help our customers deliver marketing messages so relevant that they are perceived as a service to our clients’ customers," said Yuchun Lee, CEO of Unica Corp. "Together with IBM, we will bring our leading enterprise marketing management solutions to a wider set of customers worldwide and with a much broader, more comprehensive portfolio."

At $21 per share, IBM is paying more than double Unica’s closing stock price Thursday of $9.55. It expects to close the deal sometime in the fourth quarter.

IBM said Unica’s 500 employees will be integrated into IBM’s Software Solutions Group,

In morning trading, Unica shares surged $11.22, or 117 percent, to $20.77 after setting a year high of $20.80. Shares of International Business Machines Corp. fell 55 cents to $127.75.

IBM employs some 10,000 people in Research Triangle Park, N.C.

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