Accel-KKR, a tech focused private equity firm, has completed its acquisition of Morrisville-based SciQuest Inc. for about $509 million. SciQuest’s stock has ceased trading on Nasdaq.

It is the second time the company has returned to private status following a stint on the public markets.

The company says its cloud-based, mobile-enabled, source-to-settle platform addresses all stages of procurement from the automation of core processes to enabling sophisticated, strategic and multifaceted sourcing solutions. It began

‘As a private company, we will be better able to prioritize long-term benefits and strategic goals to generate more value for customers, employees, partners and suppliers. Areas of increased emphasis include innovation, thought leadership and efficiency,’ said Stephen Wiehe, CEO of SciQuest.

SciQuest has had its ups and downs over the years. Founded in 1995 as an eCommerce business to business exchange for scientific products, it first went public in 1999. It began working on its current on demand model in 2001 and expanded its solution to serve heathcare and state and local government markets. It went private again in 2004.

CEO Wiehe engineered a turn-around for the struggling company that led it back to public markets.

In September 2010, it completed a second initial public offering of common stock, raising net proceeds of approximately $51 million prior to the redemption of our outstanding preferred stock for $36 million.

It since acquired AESoft, which sold supplier management and sourcing technology, Spend Radar, which provided spend analysis software, and Upside Software Inc. and its contract lifestyle management tech, and CombineNet, which sells advanced sourcing software, a cloud-based tool

‘We look forward to working with SciQuest to build on its foundation of delivering leading technology, customer engagement and measurable results,’ said Tom Barnds, managing director of Accel-KKR.

Accel-KKR is a technology-focused investment firm with $4.0 billion in capital commitments. The firm invests in software and IT enabled businesses well-positioned for topline and bottom-line growth.