BlackRock MuniHoldings California Quality Fund, Inc. (the Fund), formerly BlackRock MuniHoldings California Insured Fund, Inc., is a non-diversified, closed-end management investment company. The Fund's investment objective is to provide current income exempt from federal and California income taxes. The Fund invests at least 80% of its assets in investment-grade municipal obligations with remaining maturities of one year or more at the time of investment that are covered by insurance guaranteeing the timely payment of principal at maturity and interest when due. The Fund may invest directly in such securities or synthetically through the use of derivatives. It may invest in various derivative instruments, including financial futures contracts. It may invest in zero-coupon bonds. The Fund invests in sectors, such as utilities, transportation, education, health and housing. The Fund's investment advisor is BlackRock Advisors, LLC.