PIMCO Corporate & Income Opportunity Fund Reports Results for the Fiscal Quarter Ended February 28, 2013

PIMCO Corporate & Income Opportunity Fund (the "Fund") (NYSE: PTY), a diversified closed-end management investment company, which seeks maximum total return through a combination of current income and capital appreciation, today announced its results for the fiscal quarter ended February 28, 2013.

(a) Net assets are inclusive of Preferred Shares of $325 million.

(b) The information provided is in accordance with Generally Accepted Accounting Principles ("GAAP"), which requires the Fund to treat amounts accrued by the Fund under swap agreements as net realized and unrealized gain (loss). However, these amounts are treated as net income (loss) for federal income tax purposes. By using GAAP, Net Investment Income for the fiscal quarters ended February 28, 2013 and February 29, 2012 was $4,500,117 ($0.07 per common share) was $2,571,010 ($0.04 per common share) lower, respectively, and Net Realized and Change in Unrealized Gain correspondingly higher than those figures would have been if swaps amounts were treated as net investment income.

(c) Since the Fund’s net earning rates fluctuate from month to month, there will be periods when the Fund may over-earn or under-earn its monthly dividend rate. This fluctuation will have the effect of adding to or subtracting from the Fund's undistributed (overdistributed) net investment income balance. Fund management analyzes the current and projected net earning rates prior to recommending dividend amounts to the Fund's Board of Trustees for declaration. There can be no assurance that the monthly dividend rate will remain at its current level or that the undistributed net investment income balance, if any, will be sufficient to cover any shortfall in earnings to meet the current dividend rate. The undistributed (overdistributed) net investment income balance is inclusive of swap income (or loss), paydown gains and net gain (or loss) from foreign currency transactions in accordance with federal income tax treatment of these items.

Allianz Global Investors Fund Management LLC ("AGIFM"), an indirect, wholly-owned subsidiary of Allianz Asset Management of America L.P., serves as the Fund's investment manager and is a member of Munich-based Allianz Group. Pacific Investment Management Company LLC, an AGIFM affiliate, serves as the Fund's sub-adviser.

The Fund's daily New York Stock Exchange closing market price, NAV, as well as other information, is available at http://www.us.allianzgi.com/closedendfunds or by calling the Fund's shareholder servicing agent at (800) 254-5197.

The financial information contained herein is solely based upon the data available at the time of publication of this press release, and there is no assurance that any future results will be the same or similar to what is reported herein. Information that was obtained from third party sources we believe to be reliable is not guaranteed as to its accuracy or completeness. This press release contains no recommendations to buy or sell any specific securities and should not be considered investment advice of any kind. Past performance is no guarantee of future results and the investment returns generated by the Fund will fluctuate. There can be no assurance that the Fund will meet its stated objective. The Fund's ability to pay dividends to common shareholders is subject to the restrictions in its registration statement, by-laws and other governing documents, as well as the Investment Company Act of 1940. In making any investment decision, individuals should utilize other information sources and the advice of their own professional adviser.