Although change of ownership triggers reassessment of property taxes, buyers may not realize that they may have to pay supplemental tax bills. Effective January 1, 2006, AB 459--which adds Civil Code Section 1102.6c--requires sellers of residential properties of 1-4 units, or their agents, to disclose to prospective buyers that they may owe supplemental taxes. C.A.R. standard form "Notice of Your Supplemental Property Tax Bill" (SPT) will satisfy this requirement.