Bank of Scotland Corporate backed the buy. Under the terms of the deal, Whiteside and his team will take a majority equity stake. Although he declined to comment on the exact figure, he said it was "significant".
"It's been a long journey, but a successful one to complete this deal," said Whiteside.
Adare employs 1,200 staff across 17 locations, and has an annual turnover of 160m. Its operations include the Kall Kwik and Prontaprint franchises.
The MBO team comprises Whiteside, who will become chief executive officer, group purchasing director Julian Coghlan, group operations director Barry Crich, group finance director Clinton Everard, Adare Lexicon managing director Peter Livesey, Adare Label Convertors managing director David Mills and Adare Carwin managing director Stephen Ueckermann.
As part of the deal, Adare's headquarters will relocate from Dublin to the firm's largest UK site at Leeds with immediate effect.
The deal marks the completion of a strategic review that began in March last year, commissioned by owner Dublin-based private equity firm Allen, McGuire and Partners.
Corporate finance specialist Livingstone Guarantee brokered the deal, having worked before with Allen, McGuire and the Adare Group, on the sale of Adare's Great Northern Envelopes business to an MBO team in June last year.
The sale of Adare marks the last remaining divestment of Allen, McGuire and Partners' interest in print.
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