One of the early stages in establishing a business improvement district in California according to the Property and Business Improvement District Law of 1994 is to gather petitions from the property owners who would be assessed. In order for the City to proceed with the process, it's required that property owners holding more than 50% of the assessed value in the proposed district vote in favor of establishing the new BID.
This stage is required by the PBID law at Section 36621(a), which states:
Upon the submission of a written petition, signed by the property or business owners in the proposed district who will pay more than 50 percent of the assessments proposed to be levied, the city council may initiate proceedings to form a district by the adoption of a resolution expressing its intention to form a district.
Note that petitions are quite different from ballots, which are one of the final stages of BID establishment in California.