Cal. Civ. Code § 1598 : CALIFORNIA CIVIL CODE — OBLIGATIONS — CONTRACTS — NATURE OF A CONTRACT — OBJECT OF A CONTRACT — Object void

Where a contract has but a single object, and such object is unlawful, whether in whole or in part, or wholly impossible of performance, or so vaguely expressed as to be wholly unascertainable, the entire contract is void.

Ca. Civ. Code § 1598

Enacted 1872.
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