Hamer v. Sidway · New York Court of Appeals · 1891

Must the estate pay?

Short answer: Yes: giving up rights counts.

The facts. An uncle promised his teenage nephew $5,000 if he gave up drinking, smoking, swearing, and gambling until he turned 21. The nephew did it. The uncle died and the estate refused to pay, saying the clean life had only helped the nephew.

The ruling. Hamer v. Sidway (1891): The court held giving up a legal right is valid consideration for a promise, even if it benefits the person who gave it up.

The nephew's claim had been assigned to Hamer, hence the name. Nearly every American contracts class studies it.

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For fun, not legal advice.