IBM Global Services has won a contract to supply Invensys with support services for up to 10 years.
Worth as much as $100m a year, the deal will see Big Blue providing application management, helpdesk services and support for up to 29,000 workstations in a dozen countries.
As part of the deal, 600 IT staff from Invensys will be transferred to IBM's payroll. The staff will not be required to relocate, according to an Invensys spokesman.
"This is not about reducing costs," he said. "Invensys is made up of literally hundreds of businesses of all sizes, and the key thing is to try to streamline all of the business processes. There is a cost implication, but it is not the main issue."
However, Invensys has had to cut staff and costs aggressively in recent times. Last week the firm disposed of its Energy Storage group for $425m, and earlier this month said it would shed a further 2,000 staff in addition to the 3,000 it got rid of in November.
As part of the deal, IBM will supply a special 'innovation team' made up of research and development staff, consultants and business strategists to combine IT with specific Invensys projects.
Larry Lieberman, program manager at IBM's Research division, said: "Effectively, this will give our customers good access to our research department.
"Our first job will be to establish a small core of technologists and consultants to identify and address business needs. The people on this team will come from IBM and Invensys."
The deal is the third of its type for IBM Global Services this year. It closed an eight-year $1.2bn deal in January to provide support for Nextel, and signed a seven-year deal with American Express worth $4bn.
"We have been working on the deal for a year, and the expectation is that we will be working on streamlining and simplifying IT for Invensys," said an IBM Global Services spokesperson.
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