Cal. Rev. & Tax. Code § 276

(a) Except as otherwise provided by subdivision (b), for property for which the disabled veterans’ exemption described in Section 205.5 was available, but for which a timely claim was not filed, a partial exemption shall be applied in accordance with whichever of the following is applicable:
1. (1) Ninety percent of any tax, including any interest or penalty thereon, levied upon that portion of the assessed value of the property that would have been exempt under a timely and appropriate claim shall be canceled or refunded, provided that an appropriate claim for exemption is filed after 5 p.m. on February 15 of the calendar year in which the fiscal year begins but on or before the following December 10.
2. (2) If an appropriate claim for exemption is filed after the time period specified in paragraph (1), 85 percent of that portion of any tax, including any interest or penalty thereon, that was levied upon that portion of the assessed value of the property that would have been exempt under a timely and appropriate claim, shall be canceled or refunded. Cancellations made under this paragraph are subject to the provisions of Article 1 (commencing with Section 4985) of Chapter 4. Refunds issued under this paragraph are subject to the limitations periods on refunds as described in Article 1 (commencing with Section 5096) of Chapter 5.
(b) If a late-filed claim for the one-hundred-fifty-thousand-dollar ($150,000) exemption is filed in conjunction with a timely filed claim for the one-hundred-thousand-dollar ($100,000) exemption, the amount of any exemption allowed under the late-filed claim under subdivision (a) shall be determined on the basis of that portion of the exemption amount, otherwise available under subdivision (a), that exceeds one hundred thousand dollars ($100,000).
(c) For those claims filed pursuant to subdivision (a) after November 15, the exemption under that subdivision may be applied to the second installment. If that exemption is so applied, the first installment is still delinquent on December 10, and is subject to delinquent penalties provided for in this division if that installment is not timely paid. A refund shall be made to the taxpayer upon a claim submitted to the auditor if the exemption is applied to the second installment and either of the following is true:
1. (1) Both installments are paid on or before December 10.
2. (2) The reduction in taxes resulting from the exemption exceeds the amount of taxes due on the second installment.