Shoen v. Zacarias

*1114When a landowner grants someone permission to use her land, she generally retains the right to revoke that license at any time. ( Emerson v. Bergin (1888) 76 Cal. 197, 201, 18 P. 264.) The landowner may nevertheless be estopped from revoking that license-and the license will accordingly become irrevocable for "so long a time as the nature of it calls for"-if the person using the land has "expended money[ ] or its equivalent in labor" improving the land "in the execution of the license." ( Cooke v. Ramponi (1952) 38 Cal.2d 282, 286, 239 P.2d 638 ( Cooke ); Stoner v. Zucker (1906) 148 Cal. 516,…