AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON FEBRUARY 19, 2020 1933 ACT FILE NO. 333- 1940 ACT FILE NO. 811- 03763 ================================================================================ SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 _______________________ REGISTRATION STATEMENT ON FORM S-6 ________________________ FOR REGISTRATION UNDER THE SECURITIES ACT OF 1933 OF SECURITIES OF UNIT INVESTMENT TRUSTS REGISTERED ON FORM N-8B-2 A. EXACT NAME OF TRUST: GUGGENHEIM DEFINED PORTFOLIOS, SERIES 2012 B. NAME OF DEPOSITOR: GUGGENHEIM FUNDS DISTRIBUTORS, LLC C. COMPLETE ADDRESS OF DEPOSITOR'S PRINCIPAL EXECUTIVE OFFICES: Guggenheim Funds Distributors, LLC 227 West Monroe Street Chicago, Illinois 60606 D. NAME AND COMPLETE ADDRESS OF AGENT FOR SERVICE: Copies to: AMY LEE, ESQ. ERIC F. FESS, ESQ. Vice President and Secretary Chapman and Cutler LLP Guggenheim Funds Distributors, LLC 111 West Monroe Street 227 West Monroe Street Chicago, Illinois 60603 Chicago, Illinois 60606 (312) 845-3000 (630) 505-3700 It is proposed that this filing will become effective (check appropriate box) [_] immediately upon filing pursuant to paragraph (b) [_] on (date) pursuant to paragraph (b) [_] 60 days after filing pursuant to paragraph (a)(1) [_] on (date) pursuant to paragraph (a)(1) of rule 485 [_] This post-effective amendment designates a new effective date for a previously filed post-effective amendment. E. TITLE OF SECURITIES BEING REGISTERED: Units of fractional undivided beneficial interest. F. APPROXIMATE DATE OF PROPOSED SALE TO PUBLIC: As soon as practicable after the effective date of the Registration Statement. [_] Check box if it is proposed that this filing will become effective on (date) at (time) pursuant to Rule 487. ================================================================================ The registration hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a) may determine. PRELIMINARY PROSPECTUS DATED FEBRUARY 19, 2020 GUGGENHEIM DEFINED PORTFOLIOS, SERIES 2012 (the "Series") Technology Portfolio, Series 27 (the "Technology Trust") US SMID High Dividend Portfolio, Series 36 (the "US SMID High Dividend Trust") US High Dividend Strategy Portfolio, Series 36 (the "US High Dividend Strategy Trust") (A Unit Investment Trust) The above-referenced Series is comprised of the Technology Portfolio, Series 27, US SMID High Dividend Portfolio, Series 36 and US High Dividend Strategy Portfolio, Series 36 (each, a "trust" and together, the "trusts"). The attached final prospectuses for the prior series of the trusts are hereby used as the preliminary prospectus for the above-referenced Series. The narrative information and structure of the attached final prospectuses will be substantially similar to that of the final prospectus for this Series. Information with respect to pricing, the number of units, dates and summary information regarding the characteristics of securities to be deposited in this Series is not available as of this date and will be different because each series has a unique portfolio. Accordingly, the information contained herein with regard to the previous series should be considered as being included for informational purposes only. Ratings of the securities in this Series are expected to be comparable to those of the securities deposited in the previous series. The registration statement relating to the units of this Series is not complete, may be changed and is not yet effective. Information contained herein is subject to completion or amendment. The units of this Series may neither be sold nor may an offer to buy such units be accepted prior to the time the registration statement becomes effective. This prospectus shall neither constitute an offer to sell nor be considered a solicitation of an offer to buy the units. There shall be no sale of the units in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state. For purposes of the Technology Trust incorporated herein by reference are portions of the final prospectus for Guggenheim Defined Portfolios, Series 1949 (Registration No. 333-233511) as filed on October 25, 2019, which shall be used as the preliminary prospectus for such Technology Trust. For purposes of the US SMID High Dividend Trust and US High Dividend Strategy Trust incorporated herein by reference are portions of the final prospectus for Guggenheim Defined Portfolios, Series 1977 (Registration No. 333-235266) as filed on January 21, 2020, which shall be used as the preliminary prospectus for such US SMID High Dividend Trust and US High Dividend Strategy Trust. UNDERTAKING TO FILE REPORTS Subject to the terms and conditions of Section 15(d) of the Securities Exchange Act of 1934, the undersigned registrant hereby undertakes to file with the Securities and Exchange Commission such supplementary and periodic information, documents, and reports as may be prescribed by any rule or regulation of the Commission heretofore or hereafter duly adopted pursuant to authority conferred in that section. CONTENTS OF REGISTRATION STATEMENT A. Bonding Arrangements of Depositor: The Depositor has obtained the following Securities Dealer Blanket Bond for its officers, directors and employees: INSURER/POLICY NO. AMOUNT National Union Fire Insurance Company of Pittsburgh, Pennsylvania 5692790 $4,000,000 This Registration Statement comprises the following papers and documents. The Facing Sheet The Prospectus The Signatures Consents of Counsel Exhibits The following exhibits: 1.1 Reference Trust Agreement (to be supplied by amendment). 1.1.1 Standard Terms and Conditions of Trust (Reference is made to Exhibit 1.1.1 to Amendment No. 2 to the Registration Statement on Form S-6 for Claymore Securities Defined Portfolios, Series 116 (File No. 333-72828) filed on December 18, 2001). 2.1 Code of Ethics (Reference is made to Exhibit 2.1 to the Registration Statement on Form S-6 for Claymore Securities Deferred Portfolios, Series 213 (File No. 333-122184) filed on February 9, 2005). 3.1 Opinion of counsel as to legality of the securities being registered including a consent to the use of its name in the Registration Statement (to be supplied by amendment). 3.2 Opinion of counsel as to Federal and New York Income tax status of the securities being registered including a consent to the use of its name in the Registration Statement (to be supplied by amendment). 3.3 Opinion of counsel as to the Trustee and the Trust(s), including a consent to the use of its name in the Registration Statement (to be supplied by amendment). 4.1 Consent of Independent Registered Public Accounting Firm (to be supplied by amendment). 6.0 Powers of Attorney authorizing Amy Lee to execute the Registration Statement. (Reference is made to Exhibit 6.0 to Amendment No. 1 to the Registration Statement on Form S-6 for Guggenheim Defined Portfolios, Series 2001 (File No. 333-236113) filed on January 28, 2020). SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the Registrant, Guggenheim Defined Portfolios, Series 2012 has duly caused this Registration Statement to be signed on its behalf by the undersigned thereunto duly authorized, in the City of Chicago, and State of Illinois, on the 19th day of February, 2020. GUGGENHEIM DEFINED PORTFOLIOS, SERIES 2012, Registrant By: GUGGENHEIM FUNDS DISTRIBUTORS, LLC, Depositor By: /s/ Amy Lee --------------- Amy Lee Vice President and Secretary Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed below by the following persons in the capacities and on the date indicated: SIGNATURE* TITLE DATE ) ) By: /s/ Amy Lee ) ----------- ) Amy Lee ) Attorney-in-Fact* ) JERRY W. MILLER* Chief Executive Officer and ) February 19, 2020 President of Guggenheim Funds ) Distributors, LLC ) ) DOMINICK COGLIANDRO* Chief Operating Officer of ) February 19, 2020 Guggenheim Funds Distributors, ) LLC ) ) JULIE JACQUES* Treasurer of Guggenheim Funds ) February 19, 2020 Distributors, LLC ) ) JULIE JACQUES* Principal Financial Officer of ) February 19, 2020 Guggenheim Funds Distributors, ) LLC ) FARHAN SHARAFF Chief Investment Officer of Guggenheim Funds Distributors, LLC /s/ Amy Lee Vice President and Secretary of February 19, 2020 ----------- Guggenheim Funds Distributors, AMY LEE LLC ---------------------- * Executed copies of the related powers of attorney were filed as Exhibit 6.0 to Amendment No. 1 to the Registration Statement of Guggenheim Defined Portfolios, Series 2001 on January 28, 2020. CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM The consent of Grant Thornton LLP to the use of its report and to the reference to such firm in the Prospectus included in the Registration Statement will be filed as Exhibit 4.1 to the Registration Statement. CONSENT OF CHAPMAN AND CUTLER LLP The consent of Chapman and Cutler LLP to the use of its name in the Prospectus included in the Registration Statement will be contained in its opinion to be filed as Exhibits 3.1 and 3.2 to the Registration Statement. CONSENT OF DORSEY & WHITNEY LLP The consent of Dorsey & Whitney LLP to the use of its name in the Prospectus included in the Registration Statement will be contained in its opinion to be filed as Exhibit 3.3 to the Registration Statement. MEMORANDUM Re: Guggenheim Defined Portfolios, Series 2012 The list of securities comprising the trust of the fund, the evaluation, record and distribution dates and other changes pertaining specifically to the new series, such as size and number of units of the trust in the fund and the statement of financial condition of the new fund will be filed by amendment. 1940 ACT FORMS N-8A AND N-8B-2 Form N-8A and Form N-8B-2 were filed in respect of Guggenheim Defined Portfolios, Series 718 (and subsequent series) (File No. 333-169214). 1933 ACT THE INDENTURE The form of the proposed Standard Terms and Conditions of Trust is expected to be in all respects consistent with the form of the Standard Terms and Conditions of Trust dated December 18, 2001 relative to Claymore Securities Defined Portfolios, Series 116. CHAPMAN AND CUTLER LLP Chicago, Illinois February 19, 2020