To set aside a voluntary disposition for mistake in equity, the mistake must relate to the legal character or nature of the transaction or a basic matter of fact or law.
equity
Change of position is a defence to a claim in unjust enrichment for mistaken payments where the defendant has detrimentally relied on the receipt.
Unjust enrichment claims for money paid under illegal contracts may succeed if recovery is consistent with the statutory policy underlying the illegality.
Equitable compensation for breach of fiduciary duty does not require but-for causation, and a fiduciary must account for profits made in breach of their stringent obligations.
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