Cal. Rev. & Tax. Code § 20640.3

A claimant is an individual who:

(a) Holds a right to a possessory interest pursuant to a validly recorded instrument conveying such possessory interest for a term of years no less than 45 years beyond the last day of the calendar year ending immediately prior to the fiscal year for which taxes are initially postponed;

(b) Occupies as a principal place of residence the residential dwelling affixed to such possessory interest real property on the last day of the year designated in Section 20503(c) of this code;

(c) Is 62 years of age or older on or before December 31 of the fiscal year for which postponement is claimed.