European private equity firms' sales of portfolio companies to other buyout groups last year accounted for the greatest proportion of their total divestments for the first time, according to independent research conducted on behalf of the European Private Equity and Venture Capital Association.

Secondary buyouts, in which one private equity group sells an asset to another, accounted for almost a third of European divestment by value last year, more than any other form of sale, according to preliminary data produced by research provider Perep Analytics on behalf of the EVCA.