The company, best know for providing online communications services like eFax, last week disclosed a hostile bid for cloud-based storage provider Carbonite.

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The union has felt slighted by the company, claiming it agreed to deal without giving the workers time to find a competing bid, while the company doesn't want the union interfering in matters best left to shareholders and board members.

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Richard Schulze, Best Buy's founder and former chief executive, is considering a bid to take the company private.

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