Desktop publishing software house Quark has been sold to Platinum Equity, private equity group specialising in mergers and acquisitions. The Denver-Colorado based Quark group will use the additional backing to expand its digital publishing portfolio.

Financial terms of the agreement have not been disclosed.

Privately-held Quark, maker of the popular QuarkXPress desktop publishing tool, had been family owned since it was founded in the early 1980s. Founder Tim Gill sold the firm to the Ebrahimi family in 2000.

Speaking to CBR about the deal, Quark CEO Raymond Schiavone said the deal was a result of the "constraints of being family-owned. We looked at where we wanted to go in terms of digital publishing – across websites and mobile devices such as tablets – and the need to be aggressive around that area. I don’t think there is a defined leader in that market so it’s a good opportunity."

Schiavone added that the two companies will now focus on an acquisition strategy for Quark to help it attack the digital publishing market against the likes of Adobe, and expand geographically. He also confirmed job losses are unlikely.

"Quark is a legendary brand that helped create the desktop publishing market and is now helping organisations transform how they publish content both to print and digital media," said Brian Wall, partner at Platinum Equity who led the team pursuing the acquisition.

"We believe that with their expertise and innovative software, Quark has the potential to revolutionise publishing again," he added.

The deal has been completed as of August 1, 2011, Quark confirmed.