MZF Declares Monthly Dividend for July 2008

MBIA Capital/Claymore Managed Duration Investment Grade Municipal Fund (NYSE:MZF), a closed-end management investment company, has declared its monthly dividend of $0.0525 per share. This dividend represents an annualized distribution rate of 5.30% based upon the closing market price of $11.88 on June 30, 2008.

Since the Fund’s inception on August 27, 2003, through June 30, 2008, the Fund generated an average annual total return, including reinvestment of dividends, of 3.20% based on net asset value (“NAV”) and 0.28% based on market price. The Fund’s one year total return, as of June 30, 2008, was -1.29% based on NAV and -1.56% based on market price. Past performance does not guarantee future results.

The July 2008 dividend will be paid on July 15, 2008 to shareholders of record as of July 8, 2008 with an ex-dividend date of July 3, 2008. If it is determined that a notification is required pursuant to Section 19a-1 of the Investment Company Act of 1940, such notice will be posted to the Fund’s website after the close of business three business days prior to the payable date. If a distribution rate is largely comprised of sources other than income, it may not be reflective of the Fund’s performance.

MBIA Capital Management Corp. is the Fund's Investment Adviser. Based in Armonk, NY, MBIA specializes in the management of fixed-income securities, with $65 billion in fixed-income assets under management as of March 31, 2008. Founded in 1994, MBIA Capital Management Corp. maintains a particular expertise in investment-grade municipal bond investing, and is a wholly-owned subsidiary of MBIA Inc.

Claymore Securities, Inc., the Fund’s Servicing Agent, is a privately-held financial services company offering unique investment solutions for financial advisors and their valued clients. Claymore entities have provided supervision, management, servicing and/or distribution on approximately $18.4 billion in assets, as of April 30, 2008. Claymore currently offers closed-end funds, unit investment trusts and exchange-traded funds. To learn more about all of Claymore’s closed-end funds, please visit www.claymore.com/cefs. Registered investment products are sold by prospectus only and investors should read the prospectus carefully before investing.

This information does not represent an offer to sell securities of the Fund and it is not soliciting an offer to buy securities of the Fund. There can be no assurance that the Fund will achieve its investment objectives. The net asset value of the Fund will fluctuate with the value of the underlying securities. It is important to note that closed-end funds trade on their market value, not net asset value, and closed-end funds often trade at a discount to their net asset value. Past performance is not indicative of future performance. An investment in the Fund is subject to certain risks and other considerations. Such risks and considerations include, but are not limited to: Liquidity and Market Price of Shares Risk, Market Risk and Selection Risk, Municipal Bond Market Risk, Interest Rate and Credit Risk, Call and Redemption Risk, Private Activity Bonds Risk, Risks of Tobacco-Related Municipal Bonds Risk, Leverage Risk, Inflation Risk, Portfolio Strategies Risk, Derivatives Risk, Affiliated Insurers, Anti-takeover Provisions Risk and Market Disruption Risk.

Investors should consider the investment objectives and policies, risk considerations, charges and expenses of the Fund carefully before they invest. For this and more information, please contact a securities representative or Claymore Securities, Inc., 2455 Corporate West Drive, Lisle, Illinois 60532, 800-345-7999.

Member FINRA/SIPC (07/08) 926

NOT FDIC-INSURED | NOT BANK-GUARANTEED | MAY LOSE VALUE