LONDON (Dow Jones)--PAI Partners Wednesday said it has bought clinical testing company Cerba European Lab from IK Investment Partners, in the latest example of buyout firms selling companies to each other. Financial details of the transaction weren't disclosed. France-based Cerba European Lab operates in five countries, employs some 1,300 people and estimates consolidated sales of EUR250 million in 2010, including 35% from international sales. IK bought Cerba in July 2006 and built on the French-based business with further acquisitions in the country and in Belgium. PAI's cash will be used to boost the company's position in Europe. The deal is the latest in a string of transactions between private equity firms, known as secondary buyouts, and particularly in cash-generative companies where a steady income stream enables the buyer to meet interest payments on the debt used to finance a leveraged buyout. During the first quarter of the year alone there were 26 secondary buyouts globally, with a combined value of $10.1 billion. A year earlier there were nine deals totaling $1.35 billion, according to Dealogic. Business support companies in particular have attracted significant interest, especially those in the financial and clinical sectors. In March, Montagu Private Equity sold its oncology-focused diagnostic company Sebia to Cinven Group for around EUR800 million, while Royal Bank of Scotland PLC's (RBS) Global Merchant Services is moving into the final stages of a hotly contested auction that is expected to fetch as much as GBP2.5 billion. -By Marietta Cauchi, Dow Jones Newswires; +44 207 842 9241; [email protected] (END) Dow Jones Newswires June 09, 2010 07:14 ET (11:14 GMT)