Can You Claim City Parkland by Adverse Possession? The Supreme Court Weighs In

The Supreme Court of Canada (the “SCC”) recently answered an unusual question: Can a private homeowner take ownership of municipal parkland through adverse possession? In Kosicki v. Toronto (City), 2025 SCC 28, the Court said yes, in rare cases.

What Happened

• Homeowners in Toronto (the “City”) discovered that a fenced strip of their backyard actually belonged to the City as part of a park.
• That strip had been fenced off and treated as part of the private yard since the early 1970s.
• The homeowners asked the City to sell them the land, the City refused.
• The homeowners sought an order for adverse possession of the parkland.
  • Adverse possession refers to ownership of land acquired through long-term, continuous, open, and exclusive use of the land without the legal owner’s permission.

The Supreme Court’s Decision

• The SCC ruled 5–4 in favour of the homeowners.
• Ontario’s law, the Real Property Limitations Act allows ownership rights to expire if land has been exclusively possessed for at least 10 years without permission.
• Certain lands (like Crown land and road allowances) are exempt, but municipal parkland is not.
• Since the homeowners had satisfied the statutory test for adverse possession and no statutory exemption applied, the SCC held that “…the City’s title to the land was extinguished over four decades ago. To accept the City’s argument would be to interfere with the appellants’ matured possessory claim and disregard the applicable statutory scheme.”
• The dissent would have upheld the Ontario Court of Appeal’s decision and dismissed the appeal, maintaining that the Ontario Court of Appeal’s public benefit presumption was appropriate in order to protect publicly held parkland from covert privatization.

Why This Matters

• Municipalities: Municipal parkland is not automatically immune from adverse possession claims. Municipalities will need to be vigilant to prevent private encroachments from maturing into ownership claims.
• Homeowners: This case doesn’t open the floodgates. Adverse possession still requires strict proof of long, open, and exclusive use, and new claims are barred under Ontario’s land titles system.
  • Subject to s. 51 of the Land Titles Act, once a property is converted from the older Registry System to the Land Titles system, any future adverse possession claims on that land are effectively blocked.
• Policy: If governments want stronger protections for public land, they must change the law, courts won’t create new exemptions.

If you’re a landowner or municipality dealing with boundary questions, adverse possessions claims, or conflicting property interests, contact our litigation and real estate team to book a consultation.

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