Under the terms of the deal London-based ISIS has paid a £27 million purchase price, with an additional £15 million committed in ‘fire power’ to fund further acquisitions as Onyx looks to expand its geographical footprint.

To date, North Yorkshire-based Onyx has completed six acquisitions, including that of Disaster Recovery Solutions and IT business Moffat Communications, as its customer base has grown to 2,000 clients.

Mark Advani, who led the investment in Onyx for ISIS, says that technology is now making off-site hosting of data easier and more cost effective than before.

He adds: ‘The Onyx management team has done a great job of building a diverse, high service level provider of data storage and business continuity services with its existing investors.’

Founded in 1994, Onyx has ten locations in the UK and a reported turnover of £14.9 million 2010, compared to £5.7 million in 2007.

Chief executive officer of Onyx Group, Neil Stephenson, says the deal marks a ‘milestone’ for the business which will bolster its market position.

In September Onyx was named as one of the UK’s fastest growing high-tech businesses in the Sunday Times Tech Track 100, having also made the list in 2009.

The deal for Onyx follows on from ISIS’s exit of its interest in IT services business Quantix, the sixth exit completed by the firm in 2011.

Private equity firm ISIS also has interests in businesses including cycling retailers Wiggle and vehicle rental broker Nexus.