French software group Dassault Systemes (DSY.FR)and International Business Machines Corp. (IBM) said Tuesday they signed an agreement under which Dassault plans to acquire IBM's sales and client support operations for its product lifecycle management software application portfolio for approximately $600 million in cash.

The transaction, under which the two companies will integrate their PLM operations, is expected to be completed in the first half of 2010, subject to regulatory processes and other requirements.

"The planned integration of the IBM sales force and related business operations represents the largest investment in our corporate history," Bernard Charles, president and chief executive of Dassault Systemes, said in a statement.

The acquisition is expected to be accretive for earnings and operating margin from 2010, the CEO of Paris-based Dassault Systemes said during a conference call Tuesday.

As part of their planned global alliance agreement, IBM and Dassault expect to continue to jointly invest in developing, deploying and supporting client PLM environments and delivering integrated PLM solutions to their clients worldwide, the two companies said.

Charles said it was the "right time" to buy IMB's PLM portfolio after having cooperated for numerous years with IBM in the sector.

"With this announcement, IBM is evolving its partnership with DS to better align our mutual strengths and better address our clients' PLM needs," Tom Hawk, general manager, IBM Global Industrial Sector, said in the statement.

Company Web site: www.3ds.com

-By Ruth Bender and Geraldine Amiel, Dow Jones Newswires; +33 1 40 17 17 54; ruth.bender@dowjones.com; geraldine.amiel@dowjones.com