California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 11339
# (a)
Any assessment made outside of the regular assessment period may be the subject of a petition for reassessment. A petition for reassessment may be filed on or before the 50th day following the date of the notice of assessment.
# (b)
The board may extend the deadline for filing a petition for a period not to exceed 15 days, provided a written request for the extension is filed with the board on or before the expiration of the period for which the extension may be granted.
# (c)
If a petition for reassessment is not timely filed, the assessment of the board shall be final. The board may consider a petition which is not timely filed to be a claim for refund.
# (d)
The board shall hear the applicant on the petition within 90 days of the date on which the petition was filed.
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