Outsourcing giant Capita announced on Friday the acquisition of pensions administration and software business of NorthgateArinso for £27.5m."Following the acquisitions of Gissings, Higham Dunnett Shaw and Aspen over recent years, this latest deal will add new expertise and added capacity to Capita's pensions management and administration business, Capita Hartshead," the firm said.Capita Hartshead is an administrator of occupational pension schemes providing pension scheme management and administration services.NorthgateArinso - which has been purchased on a cash-free and debt-free basis - has a largely private sector client base including Aviva, Boots, Michelin and Rentokil, and made a pro forma operation profit of £4.7m on sales of £10.1m in the year ended 30 April."This acquisition will both complement our existing administration business and will allow clients coming to us from NorthgateArinso access to a wider range of specialist pension services," said chief executive of Capita Paul Pindar.Shares recovered slightly from yesterday's sell-off - on the back of half-year turnover and pre-tax profit coming in a shade below market expectations - to trade 1.75% higher at 698p at 09:33.BC