Guggenheim Funds Distributors, LLC
                           2455 Corporate West Drive
                             Lisle, Illinois 60532


                                October 11, 2013

Securities and Exchange Commission
100 F Street, N.E.
Washington, DC 20549


                 Re: Guggenheim Defined Portfolios, Series 1073
                        File Nos. 333-189800 & 811-03763
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Ladies/Gentlemen:

      The undersigned, Guggenheim Defined Portfolios, Series 1073 (the "Trust"),
by Guggenheim Funds Distributors, LLC, as the sponsor and depositor of the Trust
and of the units covered by the subject Registration Statement, pursuant to the
provisions of Rule 461 of the General Rules and Regulations of the Securities
and Exchange Commission under the Securities Act of 1933, hereby respectfully
requests that the Securities and Exchange Commission consent to the filing of
the amendment to the Registration Statement and grant acceleration of the
effectiveness of said Registration Statement, as amended, so that the same may
become effective as early as practicable on October 16, 2013 or as soon
thereafter as possible.

                                                               Very truly yours,

                                      Guggenheim Defined Portfolios, Series 1073

                                          By: Guggenheim Funds Distributors, LLC


                                                                 By: /s/ Amy Lee
                                                                 ---------------
                                                                         Amy Lee
                                                    Vice President and Secretary