California Code of Regulations
Title 2 - Administration
Division 7 - Secretary of State
Chapter 1 - Voter Registration
Article 2.5 - Statewide Voter Registration System
Section 19077 - Matching Criteria

(a) The statewide voter registration system uses a series of matching criteria, including first and last name, date of birth, address, California driver license or state identification, and the last four (4) digits of the social security number, to find and match voter records and identify them as either a high confidence or a potential match.

(b) For a potential match, the county shall evaluate the records identified as potentially matched and either accept or not accept the potential match within five (5) business days. If the potential match is accepted, the records will be merged into one voter record.

(c) If the high confidence voter records are determined to be a match, the records will be merged into one voter record.

(d) If a county elections official determines a high confidence or potential match was made in error, the county elections official shall take appropriate steps to undo the match and merge of the voter records.