US-based Donnelley, the world's largest print group, was tipped as a bidder for Huntingdon-based Astron last week, but City analysts thought it more likely that the group would be bought by either Candover or Charterhouse, who had both tabled offers of around 500m.

Astron chief executive David Mitchell (pictured) admitted the Donnelley deal had come from "left field". "Private equity was a genuine option and there was a lot of interest. But it would have been a tertiary buyout," he said. "RR Donnelley is a real safe harbour for Astron, its clients and its people. And we've got the strength of the RR Donnelley balance sheet behind us."

Mitchell, who is reported to have made 33m from the deal, plans to stay with the group, which will retain the Astron name for the foreseeable future. "We've been in permanent M&A over the past three years and the thing I'm looking forward to is running the business," he said.

Mitchell founded Astron in March 1996 with 5m of VC backing. It started out as an MBO of three print-related businesses and since then has been at the forefront of the print management and outsourcing movement.

In 2000 it merged with Tactica Solutions (formerly part of TSO) in a 92m deal backed by PPM Ventures, the private equity arm of the Prudential. It then embarked upon a period of rapid expansion, which included the acquisition of several BPO businesses from Hays, former Barclays print arm Edotech, and the mail and print division of Experian.

"If you look at the value we've created, we've gone from about a $10m business to $1bn business in less than 10 years," said Mitchell. "We're very entrepreneurial and we try and find spaces we can occupy before anyone else does."

Astron had been in a "twin-track" process since it appointed investment banks UBS and Citigroup to explore its options in February. Had a satisfactory sale not come about then Mitchell planned to float the company.

"Today [18 April] we had scheduled to push the button on the IPO," he said, dismissing City rumours that he had never intended to take the company to market. "We kept all our options open until the last possible minute, which kept the tension in it and enabled us to achieve the value we did."

Donnelley chief executive Mark A Angelson said Astron represented an "excellent strategic fit". "The Astron Group broadens our diverse printing and services capabilities in Europe, provides us with a strong operations centre in Asia, nearly doubles our size in this fast growing, high margin segment and creates an expanded opportunity to sell to existing and new clients."

Story by Lauretta Roberts