Citizens for Amending Proposition v. City of Pomona

*1165In June 1993, appellant City of Pomona (Pomona) entered into an agreement with non-party Regency Outdoor Advertising, Inc. (Regency). Pursuant to that agreement, Regency erected advertising billboards alongside several Pomona freeways. Shortly thereafter, in November 1993, the citizens of Pomona passed a ballot initiative, Proposition L (Prop. L), which prohibited the construction of additional billboards within city limits.

Pomona's agreement with Regency expired by its terms in June 2014. In July 2014, the Pomona city council adopted an ordinance purporting to amend the agreement by…