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GNMA Portfolio Series 12
File No. 33-14375
Investment Company Act No. 811-5065
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
POST-EFFECTIVE AMENDMENT NO. 6
TO 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:
DEAN WITTER SELECT GOVERNMENT TRUST*
GNMA PORTFOLIO SERIES 12
B. Name of Depositor:
DEAN WITTER REYNOLDS INC.
C. Complete address of Depositor's principal
executive office:
DEAN WITTER REYNOLDS INC.
Two World Trade Center
New York, New York 10048
D. Name and complete address of agents for service:
Mr. Michael D. Browne
Dean Witter Reynolds Inc.
Unit Trust Department
Two World Trade Center, 59th Floor
New York, New York 10048
Copy to:
Kenneth W. Orce, Esq.
Cahill Gordon & Reindel
80 Pine Street
New York, New York 10005
___________________
* Formerly the Sears Government Investment Trust.
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The Registrant has registered an indefinite number of
Units of Beneficial Interest pursuant to Rule 24f-2
promulgated under the Investment Company Act of 1940,
as amended.
Check box if it is proposed that this filing should
/x/ become effective immediately upon filing pursuant to
paragraph(b) of Rule 485.
Pursuant to the requirements of Rule 24f-2(b)(3)
promulgated under the Investment Company Act of 1940, as
amended, the election to register an indefinite number of Units
of GNMA PORTFOLIO SERIES 12 is hereby terminated
effective February 29, 1996. This Post-Effective Amendment No. 6
is being filed pursuant to Rule 485(b) promulgated under the
Securities Act of 1933, as amended, for the purpose of
terminating the Rule 24f-2 election.
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SIGNATURES
Pursuant to the requirements of the Securities Act of
1933, the registrant, Dean Witter Select Government Trust, GNMA
Portfolio Series 12, certifies that it meets all of
the requirements for effectiveness of this Registration
Statement pursuant to Rule 485(b) under the Securities Act of
1933 and has duly caused this Post-Effective Amendment No. 6 to
the Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, all in The City of New
York and State of New York on the 29th day of February, 1996.
DEAN WITTER SELECT GOVERNMENT TRUST,
GNMA PORTFOLIO SERIES 12
(Registrant)
By: DEAN WITTER REYNOLDS INC.
(Depositor)
Michael D. Browne
Michael D. Browne
Authorized Signatory
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Pursuant to the requirements of the Securities Act of
1933, this Post-Effective Amendment No. 6 to the Registration
Statement has been signed on behalf of Dean Witter Reynolds
Inc., the Depositor, by the following person in the following
capacities and by the following persons who constitute a
majority of the Depositor's Board of Directors in The City of
New York and State of New York on this 29th day of February,
1996.
DEAN WITTER REYNOLDS INC.
Name Office
Philip J. Purcell Chairman and Chief )
Executive Officer )
and Director*
Richard M. DeMartini Director*
Robert J. Dwyer Director*
Christine A. Edwards Director*
James F. Higgins Director*
Stephen R. Miller Director*
Richard F. Powers Director*
Philip J. Purcell Director*
By: Michael D. Browne
Michael D. Browne
Attorney-in-fact*
___________________
* Executed copies of the Powers of Attorney have been filed
with the Securities and Exchange Commission in connection
with the Registration Statement on Form S-6 for File No.
33-56389.
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