Torstar says the sale will strengthen the financial position of Torstar and a portion of the net proceeds will be used for debt reduction.
Harlequin, known for its romance books, has been part of Torstar for 39 years.
Torstar has said lower revenues were the primary challenge at Harlequin as the book publishing company adjusted to the digital environment.
Harlequin has more than 350 employees in Canada, and Torstar says HarperCollins has indicated that Harlequin will remain headquartered in Toronto.
Harlequin publishes the work of more than 1,300 authors and releases more than 110 titles monthly through publishing operations in 16 countries. About 95 per cent of Harlequin's revenues are from outside Canada.
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