Guggenheim Build America Bonds Managed Duration Trust Raises $340 Million from IPO

Guggenheim Build America Bonds Managed Duration Trust (NYSE: GBAB), a closed-end management investment company, announced that it has sized its initial public offering of common shares. The Trust’s common shares will begin trading on the New York Stock Exchange today under the symbol “GBAB.” The Trust's primary investment objective is to provide current income with a secondary objective of long-term capital appreciation. The Trust seeks to achieve its investment objectives by investing primarily in a diversified portfolio of Build America Bonds.

“Guggenheim is pleased to offer a convenient means of investing in the Build America Bond program, particularly at a time when we believe there is an abundance of attractive new issuance. We look forward to taking advantage of current dislocations in the municipal bond market as we invest on behalf of the closed-end fund’s shareholders,” said B. Scott Minerd, chief investment officer of Guggenheim Partners, LLC.

As the retail division of Guggenheim Partners, Guggenheim Funds Investment Advisors, LLC―the Trust’s investment adviser―and Guggenheim Funds Distributors, Inc.— the broker-dealer firm providing distribution assistance for the Trust— recently changed their respective names from Claymore Advisors, LLC and Claymore Securities, Inc. The name change was part of the integration process following the acquisition of Claymore by Guggenheim Partners in October 2009. With the launch of GBAB, the firm upholds its client-centric focus by providing individual investors exposure to investment solutions not generally available in the retail market.

“GBAB is one of the first new investment solutions rolled out under the Guggenheim Funds name and is a perfect example of the effective synergies starting to be realized across Guggenheim’s investment management platform between asset management and retail distribution,” said Steven A. Baffico, senior managing director and head of U.S. Retail for Guggenheim Funds Distributors, Inc. “We believe the tremendous success of this IPO reflects the investment community’s acknowledgement of the firms’ complementary capabilities as well as the distinct benefits the Trust offers in the current environment.”

The Trust offered 17 million shares at a price of $20 per share, representing an aggregate public offering price of $340 million, through an underwriting syndicate led by BofA Merrill Lynch, Citigroup Global Markets Inc., Morgan Stanley & Co. Incorporated, Wells Fargo Securities, LLC and Raymond James & Associates, Inc. The underwriters have the right to exercise an overallotment option which could increase the number of shares outstanding by as much as 15% within the next 45 days.

Guggenheim Funds Investment Advisors, LLC will serve as the Trust’s investment adviser. Guggenheim Partners Asset Management, LLC, the Trust’s investment sub-adviser, will be responsible for the management of the Trust's portfolio of investments. Guggenheim Funds Distributors, Inc., an affiliate of Guggenheim Funds Investment Advisors, LLC is a broker-dealer firm and acted as an underwriter and provided distribution assistance for the Trust in the offering. Guggenheim Funds Distributors, Inc., Guggenheim Funds Investment Advisors, LLC and Guggenheim Partners Asset Management, LLC are subsidiaries of Guggenheim Partners, LLC, Guggenheim Partners, LLC is a global, diversified financial services firm with more than $100 billion in assets under supervision. Guggenheim Partners, through its affiliates, provides investment management, investment advisory, insurance, investment banking, and capital markets services. The firm is headquartered in Chicago and New York with a global network of offices throughout the United States, Europe, and Asia.

There can be no assurance that the Trust will achieve its investment objectives. The value of any closed-end fund will fluctuate with the value of the underlying securities. Historically, closed-end funds often trade at a discount to their net asset value. An investment in the Trust is subject to certain risks and other considerations, including, but not limited to: Investment and Market Risk, Build America Bonds Risk, Continuation of BABs Program Risk, General Municipal Securities Market Risk, Credit Risk, Interest Rate Risk, Duration Management Risk, Financial Leverage Risk, Reinvestment Risk, Inflation/Deflation Risk, Insurance Risk, Below Investment-Grade Securities Risk, Sector Risk, Special Risks Related to Certain Municipal Securities, Asset-Backed Securities Risk, Senior Loan Risk, Liquidity Risk, Volatility Risk, Inverse Floating-Rate Securities Risk, Recent Market Developments Risks, Government Intervention in the Financial Markets Risk, Legislation Risk, Strategic Transactions Risk, Synthetic Investments Risk, Counterparty Risk, Securities Lending Risk, Investment Funds Risk, Market Discount Risk, Portfolio Turnover Risk, Market Disruption and Geopolitical Risk and Anti-Takeover Provisions Risk.

Consider the investment objectives, risks, charges and ongoing expenses of the Trust carefully before investing. The prospectus contains this and other relevant information. Please read the prospectus carefully before investing. To obtain a prospectus, visit http://www.guggenheimfunds.com or contact a securities representative or Guggenheim Funds Distributors, Inc. 2455 Corporate West Drive, Lisle, Ill. 60532, 800‐345‐7999.

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