About Guillaume

Guillaume Castonguay founded Castonguay, société d'avocats in July 2019 and practises mainly in family and civil law. A native of St-Elzéar de Témiscouata, Guillaume Castonguay earned an LL.B. from the Faculté de droit at Université Laval in 2009, completed the Barreau du Québec articling term at Cain Lamarre in Quebec City, and was admitted to the Barreau du Québec in 2011. Guillaume Castonguay then returned to the home region to practise at Moreau avocat Inc. until 2019. Guillaume Castonguay is an accredited family mediator and is regarded as a reference in family law.

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This listing was generated by AI from public sources in August 2026. It may contain errors, and we can’t guarantee it’s accurate or complete. Before you rely on anything here, verify it on their firm’s website. Confirm Guillaume Castonguay’s licence and standing in the Barreau du Québec directory ↗

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