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[Chapman & Cutler Letterhead]
May 18, 1998
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549-1004
Attn: Filing Desk, Stop 1-4
Re: Nuveen Unit Trusts, Series 12 (the "Fund")
(File No. 333-49197) (CIK No. 1038551)
Gentlemen:
On behalf of John Nuveen & Co. Incorporated, depositor of the Fund, and in
accordance with the provisions of Rule 497(j) of Regulation C under the
Securities Act of 1933 (the "Securities Act") this letter serves to certify that
the most recent amendment to the registration statement of Form S-6 for the
above captioned Trust does not differ from that which would have been filed
pursuant to Rule 497(b) of the Securities Act. Amendment No. 1 to the
registration statement, which was the most recent amendment to the registration
statement, was filed electronically with the Commission on May 14,
1998.
Very truly yours,
Chapman & Cutler
