With Postini deal, Google sharpens aim at Microsoft

SAN FRANCISCO -- Taking further aim at one of Microsoft's core franchises, Google said yesterday that it would acquire the e-mail security and management company Postini for $625 million. The deal underscores Google's ambitions to become a serious player in the business of selling software to companies and organizations, in competition with Microsoft and others.

Google, which earns most of its profit from selling ads it places next to search results and on websites, has increasingly emphasized its small but rapidly growing software business.

Earlier this year, Google chief executive Eric E. Schmidt said the company's strategy was made up of three components: "search, ads, and apps," meaning software programs.

As part of that strategy, Google has been trying to persuade businesses to replace e-mail systems and other programs with the company's own software. That package, called Google Apps, includes the Gmail service, an online calendar, and programs that can read and edit documents created with Microsoft Word and Excel.

But many businesses -- especially large ones -- are leery of moving critical functions like e-mail to Google's programs, which are delivered as services over the Web and are considered less secure than traditional software .

The acquisition of Postini, a private company whose products allow businesses to control spam and viruses, and help them to monitor and preserve e-mail messages , is an effort by Google to allay some of those concerns.

"In bigger businesses, security and compliance requirements are a must," said Dave Girouard, Google's vice president and general manager for enterprise.

If completed, the deal would be the third-largest acquisition in Google's history, after its planned $3.1 billion purchase of the online advertising company DoubleClick and its $1.65 billion deal for the video site YouTube.