The Estate of William Albin Herold claimed ownership of three islands in Lake Katchewanooka, arguing they were conveyed as part of Lot 35 by Letters Patent in 1868, despite having separated from the mainland due to rising water levels.
The application judge found in favour of the Estate, applying a "Flooding Principle" to fix the boundary and concluding that treaties with First Nations did not affect the Crown's right to sell.
The Court of Appeal allowed the appeals by the First Nations and the Attorney General of Canada, finding that the application judge made extricable errors of law by failing to objectively ascertain the parties' intentions in the Letters Patent, misapplying the Flooding Principle, and not properly considering the Crown's treaty obligations.
The appellate court concluded that the Letters Patent did not convey the islands, as they were physically separate, separately identified, and subject to specific Crown obligations under Treaty 78.