UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                   FORM 10-K/A



[ x  ]   Annual reports pursuant to section 13 or 15(d) of the Securities
         Exchange Act of 1934 for the fiscal Year ended December 31, 1999

or

[    ]   Transitional reports pursuant to section 13 or 15(d) of the Securities
         Exchange Act of 1934

         Commission File Number:   333-56240

        STRUCTURED ASSET MORTGAGE INVESTMENTS INC., MORTGAGE PASS-THROUGH
                          CERTIFICATES, SERIES 1998-12

             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)


          Delaware                                               13-3633241
(STATE OR OTHER JURISDICTION                                  (I.R.S. EMPLOYER
     OF INCORPORATION)                                       IDENTIFICATION NO.)

   383 Madison Avenue
  New York, New York                                                10179
 (ADDRESS OF PRINCIPAL                                            (ZIP CODE)
  EXECUTIVE OFFICES)

Registrants telephone number, including area code, is (212) 272-2000

Securities registered pursuant to Section 12(b) of the Act:

         None.


Securities registered pursuant to Section 12(g) of the Act:

         None.

Indicate by the check mark whether the registrant (1) has filled all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.



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<PAGE>

Yes      X                 No
        ---                     ---

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K (229.405 of this chapter) is not contained herein, and will
not be contained, to the best of the registrant's knowledge, in definitive proxy
or information statements incorporated by reference in Part III of this Form
10-K or any amendment to this Form 10-K.

         Not applicable.

State the aggregate market value of the voting and non-voting common equity held
by non-affiliates computed by reference to the price at which the common equity
was last sold, or the average bid and asked price of such common equity, as of
the last business day of the registrant's most recently completed second
business quarter.

         Not applicable.

Indicate the number of shares outstanding of each of the registrant's class of
common stock, as of the latest practicable date.

         Not applicable.

List hereunder the following documents if incorporated by reference and the Part
of the Form 10-K (e.g. Part I, Part II, etc.) into which the document if
incorporated: (1) Any annual report to security holders; (2) Any proxy or
information statement; and (2) Any prospectus filed pursuant to Rule 424(v) or
(c) under the Securities Act of 1933. The listed documents should be clearly
described for identification purposed (e.g. annual report to security holders
for fiscal year ended December 24, 1980).

         Not applicable.



                                     PART I



Item 1.  Business

         Omitted.


Item 2.  Properties

         See Item 15(a), Exhibits 99.1, 99.2, and 99.3, for information provided
         in lieu of information required in lieu of information required by Item
         102 of Regulation S-K.

Item 3.  Legal Proceedings

         The registrant knows of no material pending legal proceedings involving
         the trusts created under the Pooling and Servicing Agreements (the
         Trusts), the Trustee, the Master Servicer or the Registrant with
         respect to the Trusts other than routine litigation incidental to the
         duties of the respective parties.


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Item 4.  Submission of Matters to a Vote of Security Holders.

         None.


                                     PART II

Item 5.  Market for registrant's Common Equity and Related Stockholder Matters.

         No established public trading market for the Certificates exists.

         Records provided to the Trust by the DTC and Trustee indicate that as
         of December 31, 1998, the number of holders of record for each class of
         Certificates were as follows.

         Class A-1                  7
         Class A-2                  3
         Class A-3                  2
         Class A-4                  3
         Class A-5                  1
         Class A-6                  1
         Class A-7                  1
         Class A-8                  1
         Class A-9                  1
         Class B-1                  1
         Class B-2                  1
         Class B-3                  1
         Class B-4                  1
         Class B-5                  1
         Class B-6                  1
         Class R-I                  1
         Class R-II                 1
         Class X                    1

         Total:                     29

Item 6.  Selected Financial Data

         Omitted.

Item 7.  Management's Discussion and Analysis of Financial Conditions and
         Results of Operation.

         Omitted.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk.

         Not applicable.

Item 8.  Financial Statements and Supplementary Data.


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         See Item 15(a), Exhibits 99.1, 99.2, and 99.3, for information provided
         in lieu of information required by Item 302 of Regulation S-K.

Item 9.  Changes in and Disagreements with Accountants on Accounting and
         Financial Disclosure.

         None.

                                    PART III

Item 10. Directors and Executive Officers of the Registrant.

         Not applicable.

Item 11. Executive Compensation.

         Not applicable.

Item 12. Security Ownership of Certain Beneficial Owners and Management and
         Related Stockholder Matters.

         Not applicable.

Item 13. Certain Relationships and Related Transactions.

         Not applicable.

Item 14. Control and Procedures.

         Not applicable.

                                     PART IV

Item 15. Exhibits, Financial Statement Schedule, and reports on Form 8-K.

         (a)      Exhibits

         (99.1) Annual Independent Accountants' Servicing Reports concerning
         servicing activities for the year ended December 31, 1999.

                  a) Cendant Mortgage Corporation

         (99.2) Report of Management as to Compliance with Minimum Servicing
         Standards for the year ended December 31, 1999.

                  a) Cendant Mortgage Corporation

         (99.3) Annual Statement of Compliance under the Pooling and Servicing
         Agreement for the year ended December 31, 1999.

                  a) Cendant Mortgage Corporation




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         (99.4) Aggregate Statement of Principal and Interest Distribution to
         Certificatesholders.

         (b) On November 12, 1999, December 15, 1999 and January 14, 2000 a
         report on Form 8-K was filed by the Company in order to provide the
         statement for the monthly distributions to holders of the Certificates.
         No other reports on Form 8-K have been filed during the last quarter of
         the period covered by this report.

         (c) See (a) above.

         (d) Omitted.







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                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized:

                                      STRUCTURED ASSET MORTGAGE INVESTMENTS INC.
                                                                    (Registrant)


                                               By: /s/ Jeffrey Mayer
                                                   -----------------
                                               Name:   Jeffrey Mayer
                                               Title:  President

                                               Dated:  December 31, 2003






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                                  CERTIFICATION

I, Jeffrey  Mayer, certify that:

l. I have reviewed this annual report on Form 10-K, and all reports on Form 8-K
containing distribution or servicing reports filed in respect of periods
included in the year covered by this annual report, of Structured Asset Mortgage
Investments Inc., Mortgage Pass-Through Certificates, Series 1998-12.

2. Based on my knowledge, the information in these reports, taken as a whole,
does not contain any untrue statement of a material fact or omit to state a
material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading as of the
last day of the period covered by this annual report;

3. Based on my knowledge, the distribution or servicing information required to
be provided to the trustee by the servicer under the pooling and servicing, or
similar, agreement, for inclusion in these reports is included in these reports;

In giving the certifications above, I have reasonably relied on information
provided to me by the following unaffiliated parties:

Well Fargo Bank Minnesota, N.A., as Trustee

Date: December 31, 2003



                                           By: /s/ Jeffrey Mayer
                                               -----------------------------
                                           Name: Jeffrey Mayer
                                           Company: Structured Asset Mortgage
                                           Investments Inc.
                                           Title: President



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