Canwest, the Canadian media firm which owns 45% of TV3, is to sell its shareholding in the Irish company.
A spokesperson for Canwest said staff in Dublin were informed about the process today.
At its annual general meeting last week, Canwest's chief executive, Leonard Asper, said the company needed to reduce debt.
The sale of its TV3 holding is part of a strategy to achieve this reduction.
TV3's other shareholders are Granada Television and Windmill Lane.