Parrish joined Postmedia in 2010 in a consulting role and became the COO in January 2012, after having held various senior executive roles in digital and traditional media companies over the last two decades.
He said in a statement that with the acquisition of Sun Media complete, it was the right moment for him to take advantage of other opportunities.
President and CEO Paul Godfrey said that under Parish's leadership, Postmedia has undergone a fundamental transformation from a traditional newspaper publisher to a multi-platform media company.
Postmedia Network Inc. is a wholly-owned subsidiary of Postmedia Network Canada Corp. (TSX:PNC.B), the largest publisher by circulation of English-language daily newspapers in Canada.
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