Chapman and Cutler LLP
111 West Monroe Street
Chicago, Illinois 60603
September 6, 2013
Mr. Edward Bartz
Division of Investment Management
Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549
Re: Guggenheim Defined Portfolios, Series 1077
Income & Treasury Limited Duration Portfolio of Funds, Series 31
File Nos. 333-190225 and 811-03763
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Dear Mr. Bartz:
This letter is in response to your comments given during a telephone
conversation with our office regarding the registration statement on Form S-6
for Guggenheim Defined Portfolios, Series 1077, filed on July 29, 2013 with the
Securities and Exchange Commission (the "Commission"). The registration
statement offers the Income & Treasury Limited Duration Portfolio of Funds,
Series 31 (the "Trust").
PROSPECTUS
Investment Summary -- Principal Investment Strategy
1. Because the sponsor generally selects Closed-End Funds that hold
securities that have durations of five years or less, please change the duration
example from a three year example to a five year example.
Response: The existing example has been replaced with the following: "For
example, if a bond has a duration of 5 years and interest rates go up by 1%, it
can be expected that the bond price will move down by 5%."
We appreciate your prompt attention to this registration statement. If you
have any questions or comments or would like to discuss our responses to your
questions please feel free to contact the undersigned at (312) 845-3484.
Very truly yours,
CHAPMAN AND CUTLER LLP
By /s/ Morrison C. Warren
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Morrison C. Warren