What are the requirements for a constructive trust and a claim for the constructive trust?

As for the claim for constructive trust, counsel for the plaintiffs submits that the plaintiffs can meet the prerequisites for a constructive trust based on wrongful conduct set out in Soulos v. Korkontzilas, 1997 CanLII 346 (SCC), [1997] 2 S.C.R. 217 at 241: (1) The defendant must have been under an equitable obligation in relation to the activities giving rise to the assets in his hands; (2) The assets in the hands of the defendant must be shown to have resulted from deemed or actual agency activities of the defendant in breach of his equitable obligation to the plaintiff; (3) The plaintiff must show a legitimate reason for seeking a proprietary remedy, either personal or related to the need to ensure that others like the defendant remain faithful to their duties; and (4) There must be no factors which would render imposition of a constructive trust unjust in all the circumstances of the case. e.g., the interests of intervening creditors must be protected.