Mariella De Stefano

Lawyer, Partner and Co-chair of the Insurance Law Group


Insurance Law


English, French, Italian and Spanish





Mariella De Stefano is a partner and co-chair of our Insurance Law Group. Her practice focuses on insurance litigation and civil and professional liability, particularly in subrogation claims and complex subrogation matters.

Mariella regularly leads our Insurance Group in working with insurers, reinsurers, and insurance syndicates to pursue recovery claims in a timely and efficient manner, including by way of alternative dispute resolution . She has also acquired expertise in insurance recovery files and now heads the recovery team in our insurance department, which is mainly comprised of junior and intermediate lawyers.

Her meticulousness and organizational and analytical skills have been an asset in her diverse and complex files, often involving multiple parties and large claims. These cases have led her to appear before the courts and in settlement conferences, representing her clients’ interests both in demand and in defense.


Best Lawyers in Canada: recognized for Insurance Law since 2019


Governor of the Quebec Bar Foundation


The Lake Overflows but the Loss Is Excluded

3 August 2023

One will recall the catastrophic events of the evening of April 27 2019 when a dike collapsed in Sainte-Marthe-sur-le-Lac flooding a large neighborhood causing catastrophic damages to property. But was this loss covered by the residential policy issued by La Personnelle? That is the question the Superior Court attempted to answer in the matter of […]

An “Owner Occupant” Home Insurance Requires Actual Occupancy by the Owner

13 January 2023

On December 20, 2022, in Dang c. Industrielle-Alliance, assurance auto et habitation inc., 2022 QCCA 1739, the Court of Appeal maintained the Superior Court judgment which was the topic of our bulletin of June 17, 2021 (Homeowner Insurance Policy: The Importance of Living in the Insured Dwelling). The Superior Court Decision Appellant was the sole […]

A Wellington Application First Requires a Covered Loss

8 June 2021

In Construction Placo inc. c. Kingspan Insulated Panels Ltd., 2021 QCCS 1230, rendered on March 18, 2021, Construction Placo inc. [Placo], as cross-defendant, sought an order from the Court requesting Société d’assurance générale Northbridge [Northbridge] to assume its defence and to pay all costs associated with its defence within the scope of the cross-claim. In […]

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Publications and Conferences

Mariella co-authors the following publications, updated bi-annually:

  • Residential Insurance Policies, Annotated, Thomson Reuters / Carswell
  • Commercial Insurance Policies, Annotated, Thomson Reuters / Carswell

She also writes numerous newsletters and prepares conferences on topics such as product liability, the duty to defend, underwriting in Quebec, the assessment of bodily injuries in Quebec, and the preparation of subrogation files.

Community Involvement

Active volunteer for the Kidney Foundation of Canada


Bachelor of Common Law (LL.B.)

McGill University


Bachelor of Civil Law (B.C.L.)

McGill University


Bachelor of Arts

McGill University


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