GLOBAL - Mellon Financial Corp has taken full control of the Russell/Mellon performance measurement joint venture.

Mellon has bought Russell Investment Group's 50% share of the business for an undisclosed sum. The business, formerly known as CAPS, has 1,200 clients in Europe.

The six-year-old business will be renamed Mellon Analytical Solutions, it said. Pittsburgh-based Mellon will take on responsibility for existing Russell/Mellon locations and workforce.

Russell will continue to own Russell Indexes but will take on the sales, servicing, calculation and distribution that were contracted with the venture.

Russell will bring the management of all aspects of its index business in-house and about 30 members of the Russell/Mellon index-related team will become Russell employees.

MAS will be part of Mellon's Asset Servicing sector, which accounts for 22% of Mellon's revenue.

Mellon - in the news recently over reports it was seeking tie-ups with rivals - said MAS "will be a critical component" for its traditional custody and pension fund markets.

Russell/Mellon has more than 650 employees in five countries and more than $6trn in assets under measurement.

"This acquisition is part of our strategy of making investments to capitalize on growth opportunities in our asset management and asset servicing businesses," said Mellon chief executive Martin McGuinn.

His counterpart at Russell, Craig Ueland, said: "As Russell does in many aspects of our business, we will focus on our core strengths while relying on third-party experts like Mellon for important services that are not entirely central to our investment services offerings."