Economic duress, explained

Formulations vary by jurisdiction, but challenges of this kind typically require a wrongful or improper threat, the absence of a reasonable alternative to agreeing, and a causal link between the two and the decision to sign. Each element does independent work, and the second is usually the hardest.

A party with the option of litigating, walking away, or accepting a worse commercial outcome generally had an alternative, even if every option was bad.

Threatening to exercise a legal right, including terminating a contract or refusing further business, is ordinarily not wrongful. Nor is exploiting a counterparty's known urgency. Commercial law starts from the position that parties are free to press their advantage, and treats the signed agreement as the record of what they decided.

What the party knew at signature, what it did in the days around it, and whether it protested or reserved rights contemporaneously. Courts and tribunals examining these challenges tend to look at the conduct at the time rather than at the fairness of the terms in hindsight. That was the reasoning in the proceeding described in the case file, where the decision turned on what continued reliance was reasonable by the time the document was signed.