An Auckland-based Canadian billionaire previously linked to an alternative news venture has taken a substantial holding in media company NZME.

NZME owns the NZ Herald, BusinessDesk and Newstalk ZB.

E tū negotiator Michael Wood says many are concerned about a potential change in editorial direction.

"The concern here is that we clearly have an individual that is highly motivated to take control of a major media entity in New Zealand and who is doing so, quite clearly, with the intent of promulgating a particular political perspective." 

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