- Noreen O'Leary and Andrew McMains

NEW YORK In a major realignment of its agency roster, Microsoft is shifting ad chores on its Office business suite to WPP Group's JWT.

Microsoft today confirmed that it would now work with JWT on Office and issued this brief statement: "On the creative side, we work with a roster of great agencies on different brands and campaigns. In this rapidly changing media climate, we will continue our philosophy of shifting assignments based on business needs. JWT will be doing work for us on the Office business."

Office had been handled previously by Interpublic Group's McCann Erickson. This marks the second major Microsoft loss for IPG of late following the software giant's recent decision to pull its global direct marketing assignment from MRM.

The Office shift follows a pitch for a new Microsoft mobile offering won by McCann's T.A.G. unit, said sources. JWT, McCann and fellow roster shop Crispin, Porter + Bogusky competed for that assignment, for which the client used the code-name Pink. (Adweek.com reported that T.A.G. won Pink yesterday.)

JWT, which first joined the roster about a year ago, now handles three key Microsoft assignments: "People ready," the new Bing search engine and Office. The shop declined to comment.

McCann also declined to comment and referred queries to Microsoft, where a rep indicated that the company would not discuss products until they were in the marketplace. McCann still handles Windows mobile efforts, and its T.A.G. unit has Xbox in addition to Pink.

Spending for Pink could not be ascertained in part because the assignment is new. In the U.S., Windows major media spending totaled $62 million last year and $70 million in the first four months of 2009, according to Nielsen. Those figures don't included online spending.

All told, Microsoft spent nearly $260 million in the U.S last year and about $118 million between January and April this year, per Nielsen.

In the last 19 months, Microsoft has reached beyond its lead agency McCann for new ideas for key assignments.

In February 2008, Crispin joined the Microsoft roster, landing the $300 million Windows consumer products assignment; in July, JWT broke into Microsoft's ranks, taking the $150 million "People ready" business from McCann. In April of this year, JWT won creative duties on a $100 million assignment for a new search product that turned out to be Bing.

McCann competed for the previous tasks but hadn't prevailed until the "Pink" pitch.

Separately, sources said McCann's San Francisco operations would lay off around 50 people, or 10 percent of its staff, in mid-July.

This story updates and replaces an item posted yesterday with the client's confirmation.

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