California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 606
# (a)
Except as provided in subdivisions (b) and (c), when any tract of land is situated in two or more revenue districts, the part in each district shall be separately assessed.
# (b)
Where the owner of two or more contiguous parcels comprising the tract is identical, and the full value of any parcel is less than fifty thousand dollars ($50,000), that parcel may be combined with the contiguous parcel with the greatest assessed valuation.
# (c)
Where the owner of two or more contiguous parcels comprising the tract is identical, and the tract of land is being used for a single-family residence and constitutes 45,000 square feet or less, the smallest parcel may be combined with the largest contiguous parcel.
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