California Bank of Commerce NOTES TO FINANCIAL STATEMENTS 3.  INVESTMENT SECURITIES Available-for-Sale The amortized cost and estimated fair value of available-for-sale investment securities at December  31, 2011 and 2010 consisted of the following: Net unrealized gains on available-for-sale investment securities totaling $370,843 were recorded, net  of $152,046 in tax liabilities, as accumulated other comprehensive income within shareholders’ equity  at December 31, 2011. Unrealized holding gains arising during the year ended December 31, 2011  totaled $206,944. Proceeds from the maturity of available-for-sale investment securities for the year ended December  31, 2011 totaled $27,926,462. Proceeds and gross realized gains from the sale of available-for- sale investment securities for the year ended December 31, 2011 totaled $3,950,521 and $124,100,  respectively. Net unrealized gains on available-for-sale investment securities totaling $287,999 were recorded, net  of $118,080 in tax liabilities, as accumulated other comprehensive income within shareholders’ equity  at December 31, 2010. Unrealized holding gains arising during the year ended December 31, 2010  totaled $280,978. Proceeds from the maturity of available-for-sale investment securities for the year  ended December 31, 2010 totaled $1,595,953. Proceeds and gross realized gains from the sale of  available-for-sale investment securities for the year ended December 31, 2010 totaled $10,862,782  and $372,895 respectively. 30 2010 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains Losses Value Debt securities: U.S. Government agencies $ 2,000,000 $ 1,638 $ - $ 2,001,638 Mortgage-backed securities -  residential 20,571,619 287,369 (1,008)  20,857,980 Other securities: Money Market mutual funds  27,500,000 - - 27,500,000 $ 50,071,619 $ 289,007 $ (1,008) $ 50,359,618 2011 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains Losses Value Debt securities: Mortgage-backed securities -  residential $ 35,978,823 $ 461,911 $ (91,068) $ 36,349,666