A recent Ontario Superior Court decision offers important guidance for estate and family property disputes involving constructive trust claims and contested possession of real property. In Fournier v. Giannousopoulos, 2026 ONSC 2813, the Court ordered vacant possession and sole carriage of sale in favour of a sole registered owner, notwithstanding her former common law partner’s unresolved constructive trust and joint family venture (“JFV”) claims. The decision reinforces a clear and practical principle: asserting an equitable interest in property is not a licence to remain in possession indefinitely while the registered owner bears the full financial burden of carrying that property.
Although the case arises in a family law context, its reasoning maps directly onto estate disputes — particularly those involving beneficiaries, surviving partners, or other claimants who assert constructive trust interests over estate-owned real property while resisting sale or administration.
Case Summary
Kelsy Fournier solely owned a residential property at 78 Squires Avenue, Toronto. She and Markos Giannousopoulos, her former common law partner and the father of their twin daughters, had cohabited there during their relationship. Following their separation in November 2024, Markos remained in the property while Kelsy moved out as part of a CAS safety plan.
For 17 months post-separation, Kelsy paid 100% of all property-related expenses totalling $76,567 on a net after-tax basis. She repeatedly sought Markos’ cooperation in listing the property for sale. He refused to engage. When BMO declined to renew the mortgage, and multiple alternative lenders rejected her applications, Kelsy brought a motion for vacant possession and sole carriage of sale.
Markos opposed the motion, asserting a constructive trust interest and a joint family venture claim based on alleged contributions to the property — including commission rebates as the parties’ real estate agent, renovation labour, and contributions to a prior condominium. He argued that selling the property before trial would prejudice his proprietary interests and that the motion was vindictive. He also raised the prospect of homelessness.
Does an Unresolved Constructive Trust Claim Prevent Sale?
The court’s answer was an unequivocal no. In Ontario, unmarried spouses have no statutory property rights equivalent to those available to married spouses under the Family Law Act. A person not on title must rely entirely on equitable remedies — constructive trust or unjust enrichment — to assert any claim to property held in another’s name. Similar remedies apply to common law spouses in estates matters.
Critically, the decision confirms that registered sole owners can obtain vacant possession and an order for sale despite an occupying party’s unresolved constructive trust claim. Alternatively, the court may order that the net proceeds of sale be held in trust pending trial, thereby preserving the claimant’s alleged interest in value without tethering it to the physical property.
The court was explicit that even if Markos ultimately succeeded on his constructive trust or JFV claims, his remedy could be limited to a monetary award rather than a proprietary interest in the Squires Property. This is a critical point. Where a court finds unjust enrichment, they look to monetary remedies in priority to proprietary interests. The mere possibility of a proprietary remedy will not necessarily result in the preservation of the asset in specie.
Why This Decision Matters for Estate Disputes
The Constructive Trust Claimant Cannot Use Possession as Leverage
The most transferable principle from Fournier is this: possession of property is not a proxy for ownership, and courts will not allow an occupant to use physical control of an asset as leverage while the registered owner — or, in the estate context, the estate — bears the carrying costs.
In estate disputes, this scenario arises frequently. A surviving common law partner, an adult child, or another person may be living in estate-owned real property and asserting a constructive trust interest. They may resist sale on the basis that their equitable claim has not yet been adjudicated. Fournier confirms that this resistance will not likely succeed where:
- The registered owner (or estate) is bearing the financial burden of the property;
- The claimant’s alleged interest can be adequately protected by holding net sale proceeds in trust; and
- There is no compelling reason why the claimant’s remedy, if proven, must be proprietary rather than monetary.
Constructive Trusts Remains Discretionary and Remedial
Fournier is a useful reminder that a constructive trust argument is not a trump card. Even a claimant with a credible unjust enrichment argument faces two further hurdles: first, establishing that a monetary remedy is inadequate; and second, demonstrating a sufficient nexus between their contributions and the specific property claimed. Courts retain full discretion to award money rather than a proprietary interest, and the existence of an unresolved claim does not, without more, justify blocking sale or continued occupation.
Conclusion
Fournier v. Giannousopoulos, 2026 ONSC 2813 is a clear and practically useful decision for anyone navigating estate disputes where a constructive trust claimant is in possession of real property and resisting sale. Estate trustees facing similar resistance from occupants asserting equitable interests now have strong authority to bring motions for vacant possession, sole carriage of sale, and an order that net proceeds be held in trust pending a hearing.
This blog is intended for general informational purposes does not constitute legal advice.