EX-24 2 poas.txt POWER OF ATTORNEY Each of the undersigned, being a person required to file a statement under Section 16(a) of the Securities Exchange Act of 1934, as amended (the '1934 Act'), with respect to Guggenheim Build America Bonds Managed Duration Trust, a Delaware statutory trust, hereby authorizes, designates and appoints Kevin M. Robinson and Mark E. Mathiasen to act as attorney-in-fact to execute and file statements on Form 3, Form 4 and Form 5 and any successor forms adopted by the Securities Exchange Commission, as required by the 1934 Act and the Investment Company Act of 1940, as amended, and the rules thereunder, and to take such other actions as such attorney-in-fact may deem necessary or appropriate in connection with such statements, hereby confirming and ratifying all actions that such attorney-in-fact has taken or may take in reliance hereon. This power of attorney shall continue in effect until the undersigned no longer has an obligation to file statements under the section cited above, or until specifically terminated in writing by the undersigned. This Power of Attorney may be exectued in multiple counterparts, each of which shall be deemed an origianl, but which taken together shall constitute one instrument. IN WITNESS WHEREOF, each of the undersigned has duly executed this Power of Attorney on the 23rd day of September 2010. Signature /s/ Randall C. Barnes ------------------------- /s/ Roman Friedrich III -------------------------- /s/ Ronald A. Nyberg -------------------------- /s/ Ronald E. Toupin, Jr. -------------------------- /s/ Robert B. Karn III -------------------------- /s/ J. Thomas Futrell -------------------------- /s/ Steven M. Hill -------------------------- /s/ Kevin M. Robinson -------------------------- /s/ Mark E. Mathiasen -------------------------- /s/ Bruce Saxon -------------------------- /s/ Melissa J. Nguyen -------------------------- /s/ Elizabeth H. Hudson -------------------------- /s/ James Howley -------------------------- /s/ Mark J. Furjanic -------------------------- /s/ Donald P. Swade -------------------------- /s/ B. Scott Minerd -------------------------- /s/ James E. Pass -------------------------- /s/ Bruce Albelda -------------------------- /s/ Anne Bookwalter Walsh --------------------------