Rev. & Tax. Code, § 4527

(a) The tax collector shall pay to the holder of a tax certificate, from amounts on deposit in the Tax Certificate Redemption Fund, an amount equal to the purchase price of the tax certificate, together with interest thereon at a rate equal to the rate the county would have to pay on any refund to a taxpayer for the same fiscal year, that rate to be applied to all amounts paid with respect to the certificate from the date of the sale of the tax certificate, and shall cancel the tax certificate if any of the following occur:

(1) The taxes and assessments assigned by the tax certificate had been paid prior to the sale of the tax certificate.

(2) After the sale of the tax certificate, the taxes and assessments assigned by the tax certificate are canceled for any reason other than the payment of the taxes and assessments.

(3) The lien on the parcel specified in the tax certificate is removed, other than pursuant to Section 2195 or 4105.2, or by order of the federal bankruptcy court, prior to the time the holder of the tax certificate has received all amounts due under the tax certificate.

(4) The parcel specified in the tax certificate is deeded to a taxing agency pursuant to Chapter 8 (commencing with Section 3771) of Part 6.

(5) Upon the request of the holder of the tax certificate, when there has been a violation of Section 3441 with respect to the parcel specified in the tax certificate.

(b) Promptly after obtaining knowledge of any occurrence described in subdivision (a), the tax collector shall notify, in writing, the holder of the applicable tax certificate.

(c) If the delinquency penalty assigned by a tax certificate is canceled pursuant to Section 2610.5 or Section 4985.2, or for any other reason other than the payment in full of the penalty, then, at the option of the holder of the tax certificate, the tax collector shall, from amounts on deposit in the tax certificate redemption fund, do either of the following:

(1) Pay to the holder of the tax certificate an amount equal to the purchase price of the tax certificate, together with interest thereon at a rate equal to the rate the county would have to pay on any refund to a taxpayer for the same fiscal year, that rate to be applied to all amounts paid in respect of the certificate from the date of the sale of the tax certificate, and cancel the tax certificate.

(2) Pay to the holder of the tax certificate an amount equal to the difference between the purchase price of the tax certificate and the total amount of taxes and assessments assigned by the tax certificate, together with interest on that amount at a rate equal to the rate the county would have to pay on any refund to a taxpayer for the same fiscal year, that rate to be applied to all amounts paid in respect of the certificate from the date of the sale of the tax certificate, and adjust the information contained in the tax certificate and the tax certificate record accordingly.

(d) If a redemption certificate is issued pursuant to Section 4105.2 with respect to a parcel specified in a tax certificate, and all amounts assigned under the tax certificate, including, without limitation, amounts due under Section 4103, are not paid to the holder of the tax certificate, the tax collector shall immediately pay to the holder of the tax certificate, from amounts on deposit in the Tax Certificate Redemption Fund, any amount so assigned but not paid.

(e) The tax collector may use amounts on deposit in the Tax Certificate Redemption Fund to make the payments permitted under Sections 3729, 3731, 4920, and 5103.