Riverbed has purchased Zeus, which claims to be a pioneer of application delivery controller software, for about $110 million (£68.3 million) in cash and up to a further $30 million if performance goals are reached in the next year.

Founded in 1995, Cambridge-based Zeus delivers high performance software-based load balancing and traffic management solutions for virtual and cloud environments. The business assists clients in delivering applications and websites with a consistent user-experience.

Following the deal – which was DFJ Esprit’s fifth exit of the year and earned the firm a 15-times return – Zeus will become a new business unit of Riverbed, which will be led by the former chief executive of the company Jim Darragh.

Darragh comments, ‘There is great synergy between our technologies, employees and corporate strategies, and we share Riverbed’s vision of delivering performance solutions for all applications.’

The deal was announced as Riverbed closed a second acquisition as part of its consolidation strategy. The business has purchased New Zealand web content optimisation business Aptimize.

DFJ Esprit led a re-capitalisation of Zeus in 2004, with SEP leading a £3 million Series A fundraising round in 2005. The company’s major clients include Amazon, Gilt Group, Rackspace, Joyent, BBC, ITV, Domino’s Pizza and Virgin Media.

Andrew Davison, a partner at SEP adds, ‘When we invested in Zeus six years ago, we were confident that the company had some very strong technology, addressing a significant potential market opportunity. Since then, we have been very closely involved, helping to build a much more substantial business and a more robust strategy. We are pleased to see our efforts pay off.’