UNITED STATES ~~SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 ____~~

~~FORM 10-K FOR~~SECURITIES ~~ANNUAL~~ AND ~~TRANSITION REPORTS PURSUANT TO SECTIONS 13 OR 15(d) OF THE SECURITIES~~ EXCHANGE ~~ACT OF 1934~~COMMISSION

WASHINGTON, D.C. 20549

FORM 10‑K

FOR ANNUAL AND TRANSITION REPORTS

PURSUANT TO SECTIONS 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

(Mark One)

	x	ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
	For the fiscal year ended December 31, 2014
or
	o	TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

☒

ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2015

☐

TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ________ to ________

Commission File Number of issuing entity: 001-33605 STRATS Trust for AMBAC Financial Group, Inc. Securities, Series 2007-1 (Exact name of issuing entity as specified in its charter) Commission File Number of depositor and sponsor: 001-31818 Synthetic Fixed-Income Securities, Inc. (Exact name of depositor and sponsor as specified in its charter)

New York	20-7474289
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
301 South College Street, Charlotte, North Carolina	28288
(Address of principal executive offices)	(Zip Code)

Central Index Key Number of issuing entity: 0001405198

STRATS Trust for AMBAC Financial Group, Inc. Securities, Series 2007-1

(Exact name of issuing entity as specified in its charter)

Commission File Number of depositor and sponsor: 001-31818

Central Index Key Number of depositor and sponsor: 0001140396

Synthetic Fixed-Income Securities, Inc.

(Exact name of depositor and sponsor as specified in its charter)

New York	20-7474289
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

301 South College Street, Charlotte, North Carolina	28288
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code: (212) 214-6277

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

Title of each class	Name of Registered exchange on which registered

STRATS Certificates, Series 2007-1	New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None.

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ~~Yes o No x~~

~~Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.~~ Yes o ☐ No x☒

Indicate by check mark ~~whether~~if the registrant: ~~(1) Has filed~~is ~~all~~not ~~reports~~ required to befile ~~filed~~reports bypursuant ~~section~~ to Section 13 or Section 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~~. ~~Yes x No o~~

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes x ☐ No o☒

Indicate by check mark ifwhether ~~disclosure~~the ofregistrant: ~~delinquent~~(1) ~~filers~~Has ~~pursuant~~ filed all reports required to ~~Item~~be ~~405~~filed ofby ~~Regulation~~section ~~S-K~~13 isor ~~not~~15(d) ~~contained~~of ~~herein,~~the ~~and~~Securities ~~will~~Exchange ~~not~~Act beof ~~contained,~~1934 toduring the ~~best~~preceding of12 ~~registrant’s~~months ~~knowledge, in~~(or ~~definitive~~for ~~proxy~~such orshorter ~~information~~period ~~statements~~that ~~incorporated~~the byregistrant ~~reference~~was inrequired ~~Part~~to ~~III~~file ofsuch ~~this~~reports), ~~Form~~and ~~10-K~~(2) orhas ~~any~~been ~~amendment~~subject to ~~this Form~~such ~~10-K. Not~~filing ~~applicable~~requirements for the past 90 days.

~~Indicate~~Yes by☒ No check mark whether the registrant is large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definition of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.☐

~~Large~~Indicate ~~accelerated~~by ~~filer~~check ~~o Accelerated~~mark ~~filer~~whether ~~o Non~~the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T ~~accelerated~~(§ ~~filer~~232.405 ~~x Smaller~~of ~~reporting~~this ~~company~~chapter) oduring the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

~~Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).~~ Yes o ☒ No x☐

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S‑K is not contained herein, and will not be contained, to the best of 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.

Indicate by check mark whether the registrant is large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definition of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b‑2 of the Exchange Act.

Large accelerated filer ☐

Accelerated filer ☐

Non- accelerated filer ☒

Smaller reporting company ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).

Yes ☐ No ☒

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 fiscal quarter:

The registrant has no voting stock or class of common stock that is held by non-affiliates.

DOCUMENTS INCORPORATED BY REFERENCE

None.

Introductory Note

Synthetic Fixed-Income Securities, Inc. (the “Depositor”) is the Depositor in respect of the STRATS Trust for AMBAC Financial Group, Inc. Securities, Series 2007-1 (the “Trust”), a common law trust formed pursuant to the Base Trust Agreement, dated as of September 8, 2006, between the Depositor and U.S. Bank Trust National Association, as trustee (the “Trustee”), as supplemented by the STRATS Certificates Series Supplement 2007-1 (the “Series Supplement”) dated as of July 16, 2007 in respect of the Trust. The Trust’s assets consist solely of DISCS issued by Ambac Financial Group Inc. The Certificates do not represent obligations of or interests in the Depositor or the Trustee.

Pursuant to staff administrative positions established in Corporate Asset Backed Corporation (available August 9, 1995), the Trust is not required to respond to various items of Form 10‑K. Such items are designated herein as “Not Applicable.” Distribution reports detailing receipts and distributions by the Trust are filed after each distribution date on Form 10-D in lieu of reports on Form 10‑Q. AMBAC Financial Group, Inc., the issuer of the underlying securities, is subject to the information reporting requirements of the Securities Exchange Act of 1934 (the “Exchange Act”). For information on AMBAC Financial Group, Inc. please see its periodic and current reports filed with the Securities and Exchange Commission (the “Commission”) under its Exchange Act file number, 001-10777. The Commission maintains a site on the World Wide Web at “http://www.sec.gov” at which users can view and download copies of reports, proxy and information statements and other information filed electronically through the Electronic Data Gathering, Analysis and Retrieval system, or “EDGAR.” Periodic and current reports and other information required to be filed pursuant to the Exchange Act by AMBAC Financial Group, Inc. may be accessed on this site. You can request copies of these documents, upon payment of a duplicating fee, by writing to the SEC. The public may read and copy any materials filed with the Commission at the Commission’s Public Reference Room at 100 F Street, NE, Washington, DC 20549. The public may obtain information on the operation of the Public Reference Room by calling the Commission at 1-800-SEC-0330. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the SEC's public reference rooms. Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee has participated in the preparation of such reporting documents, or made any due diligence investigation with respect to the information provided therein. Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee has verified the accuracy or completeness of such documents or reports. There can be no assurance that events affecting the issuer of the underlying securities or the underlying securities themselves have not occurred or have not yet been publicly disclosed which would affect the accuracy or completeness of the publicly available documents described above.

Pursuant to staff administrative positions established in Corporate Asset Backed Corporation (available August 9, 1995), the Trust is not required to respond to various items of Form 10-K. Such items are designated herein as “Not Applicable.” Distribution reports detailing receipts and distributions by the Trust are filed after each distribution date on Form 10-D in lieu of reports on Form 10-Q. AMBAC Financial Group, Inc., the issuer of the underlying securities, is subject to the information reporting requirements of the Securities Exchange Act of 1934 (the “Exchange Act”). For information on AMBAC Financial Group, Inc. please see its periodic and current reports filed with the Securities and Exchange Commission (the “Commission”) under its Exchange Act file number, 001-10777. The Commission maintains a site on the World Wide Web at “http://www.sec.gov” at which users can view and download copies of reports, proxy and information statements and other information filed electronically through the Electronic Data Gathering, Analysis and Retrieval system, or “EDGAR.” Periodic and current reports and other information required to be filed pursuant to the Exchange Act by AMBAC Financial Group, Inc. may be accessed on this site. You can request copies of these documents, upon payment of a duplicating fee, by writing to the SEC. The public may read and copy any materials filed with the Commission at the Commission’s Public Reference Room at 100 F Street, NE, Washington, DC 20549. The public may obtain information on the operation of the Public Reference Room by calling the Commission at 1-800-SEC-0330. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the SEC’s public reference rooms. Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee has participated in the preparation of such reporting documents, or made any due diligence investigation with respect to the information provided therein. Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee has verified the accuracy or completeness of such documents or reports. There can be no assurance that events affecting the issuer of the underlying securities or the underlying securities themselves have not occurred or have not yet been publicly disclosed which would affect the accuracy or completeness of the publicly available documents described above.

PART I

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 1. Business.

Item 1A. Risk Factors.

Item 2. Properties.

Item 3. Legal Proceedings.

Item 1B. Unresolved Staff Comments.

Not Applicable.

Item 4. Mine Safety Disclosures.

Not Applicable.

PART II

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Item 6. Selected Financial Data.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

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

Item 8. Financial Statements and Supplementary Data.

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

Item 9A. Controls and Procedures.

Item 9B. Other Information.

None.

PART III

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 10. Directors, Executive Officers and Corporate Governance.

Item 11. Executive Compensation.

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

Item 13. Certain Relationships and Related Transactions, and Director Independence.

Item 14. Principal Accounting Fees and Services.

SUBSTITUTE INFORMATION PROVIDED IN ACCORDANCE WITH GENERAL INSTRUCTION J(2) TO FORM 10-K.

Item 1112(b) of Regulation AB.	Significant Obligors of Pool Assets (Financial Information).
The primary asset of the issuing entity is the underlying securities, $37,500,000 of 6.15% DISCS due February 15, 2037 issued by AMBAC Financial Group, Inc. The issuer of the underlying securities, therefore, may be considered a significant obligor. The issuer of the underlying securities is subject to the information reporting requirements of the Securities Exchange Act of 1934 (the “Exchange Act”). For information on the issuer of the underlying securities please see its periodic and current reports filed with the Securities and Exchange Commission (the “Commission”) under its Exchange Act file number, 001-10777.
Item 1114(b)(2) of Regulation AB.	Credit Enhancement and Other Support, Except for Certain Derivatives Instruments (Information Regarding Significant Enhancement Providers Financial Information).
Based on the standards set forth in Item 1114(b)(2) of Regulation AB, no information is required in response to this Item.
Item 1115(b) of Regulation AB.	Certain Derivatives Instruments (Financial Information).
Based on the standards set forth in Item 1115(b) of Regulation AB, no information is required in response to this Item.
Item 1117 of Regulation AB.	Legal Proceedings.
There are no legal proceedings pending, or any proceedings known to be contemplated, by governmental authorities against the depositor, the Trustee or the issuing entity, or any property thereof, that is material to the holders of the Certificates.
Item 1119 of Regulation AB.	Affiliations and Certain Relationships and Related Transactions.
Based on the standards set forth in Item 1119 of Regulation AB, no information is required in response to this Item.
Item 1122 of Regulation AB.	Compliance with Applicable Servicing Criteria
U.S. Bank Trust National Association has been identified by the registrant as a party participating in the servicing function with respect to the pool assets held by STRATS Trust for AMBAC Financial Group, Inc. Securities, Series 2007-1. U.S. Bank Trust National Association has completed a report on an assessment of compliance with the servicing criteria applicable (the “Report on Assessment”) as of February [ ], 2015 and for a period beginning January 1, 2014 through and including December 31, 2014, which Report on Assessment is attached as an exhibit to this Form 10-K. In addition, U.S. Bank Trust National Association has provided an attestation report (the “Attestation Report”) by a registered independent public accounting firm regarding its related Report on Assessment. The Attestation Report is attached as an exhibit to this Form 10-K. Neither the Report on Assessment or the related Attestation Report has identified any material instances of noncompliance with the servicing criteria described in the Report on Assessment as being applicable to U.S. Bank Trust National Association.
Item 1123 of Regulation AB.	Servicer Compliance Statement.
U.S. Bank Trust National Association has provided a statement of compliance (the “Compliance Statement”) for the period from and including January 1, 2014 through and including December 31, 2014, which has been signed by an authorized officer of U.S. Bank Trust National Association. The Compliance Statement of U.S. Bank Trust National Association is attached as an exhibit to this Form 10-K.

Item 1112(b) of Regulation AB.

Significant Obligors of Pool Assets (Financial Information).

5The primary asset of the issuing entity is the underlying securities, $37,500,000 of 6.15% DISCS due February 15, 2037 issued by AMBAC Financial Group, Inc. The issuer of the underlying securities, therefore, may be considered a significant obligor. The issuer of the underlying securities is subject to the information reporting requirements of the Securities Exchange Act of 1934 (the “Exchange Act”). For information on the issuer of the underlying securities please see its periodic and current reports filed with the Securities and Exchange Commission (the “Commission”) under its Exchange Act file number, 001-10777.

Item 1114(b)(2) of Regulation AB.

Credit Enhancement and Other Support, Except for Certain Derivatives Instruments (Information Regarding Significant Enhancement

Providers Financial Information).

Based on the standards set forth in Item 1114(b)(2) of Regulation AB, no information is required in response to this Item.

Item 1115(b) of Regulation AB.

Certain Derivatives Instruments (Financial Information).

Based on the standards set forth in Item 1115(b) of Regulation AB, no information is required in response to this Item.

Item 1117 of Regulation AB.

Legal Proceedings.

There are no legal proceedings pending, or any proceedings known to be contemplated, by governmental authorities against the depositor, the Trustee or the issuing entity, or any property thereof, that is material to the holders of the Certificates.

Item 1119 of Regulation AB.

Affiliations and Certain Relationships and Related Transactions.

Based on the standards set forth in Item 1119 of Regulation AB, no information is required in response to this Item.

Item 1122 of Regulation AB.

Compliance with Applicable Servicing Criteria

U.S. Bank Trust National Association has been identified by the registrant as a party participating in the servicing function with respect to the pool assets held by STRATS Trust for AMBAC Financial Group, Inc. Securities, Series 2007-1. U.S. Bank Trust National Association has completed a report on an assessment of compliance with the servicing criteria applicable (the “Report on Assessment”) as of February 26, 2016 and for a period beginning January 1, 2015 through and including December 31, 2015, which Report on Assessment is attached as an exhibit to this Form 10-K. In addition, U.S. Bank Trust National Association has provided an attestation report (the “Attestation Report”) by a registered independent public accounting firm regarding its related Report on Assessment. The Attestation Report is attached as an exhibit to this Form 10-K. Neither the Report on Assessment or the related Attestation Report has identified any material instances of noncompliance with the servicing criteria described in the Report on Assessment as being applicable to U.S. Bank Trust National Association.

Item 1123 of Regulation AB.

Servicer Compliance Statement.

U.S. Bank Trust National Association has provided a statement of compliance (the “Compliance Statement”) for the period from and including January 1, 2015 through and including December 31, 2015, which has been signed by an authorized officer of U.S. Bank Trust National Association. The Compliance Statement of U.S. Bank Trust National Association is attached as an exhibit to this Form 10-K.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

(a)

The following documents have been filed as part of this report.

None.

Exhibits:

31.1 – Certification by Director of the Registrant pursuant to 15 U.S.C. Section 7241, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

33.1 – Report on Assessment of Compliance with Servicing Criteria for U.S. Bank Trust National Association for the period from and including January 1, ~~2014~~2015 through and including December 31, ~~2014~~2015.

34.1 – Attestation Report of Ernst & Young LLP on Assessment of Compliance with Servicing Criteria relating to U.S. Bank Trust National Association. ~~35.1 – Servicer Compliance Statement of U.S. Bank Trust National Association for the period from and including January 1, 2014 through and including December 31, 2014.~~

35.1 – Servicer Compliance Statement of U.S. Bank Trust National Association for the period from and including January 1, 2015 through and including December 31, 2015.

(b)

See Item 15(a) above.

(c)

Not Applicable.

SIGNATURE

Pursuant to the requirements of Section 13 or 15(d) 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.

Synthetic Fixed-Income Securities, Inc., as Depositor for the Trust By: /s/ Barbara Garafalo Name: Barbara Garafalo Title: Vice President (senior officer in charge of the securitizations of the depositor)

ByDated: ~~/s/~~ March ~~Barbara~~30, ~~Garafalo Name: Barbara Garafalo Title: Vice President~~2016

~~(senior officer in charge of the securitizations of the depositor)~~6

Dated: March 31, 2015

EXHIBIT INDEX

Exhibit Number in this Form 10-K	Description of Exhibits
Exhibit Number in this Form 10‑K	Description of Exhibits
31.1	Certification by Director of the Registrant pursuant to 15 U.S.C. Section 7241, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
33.1	Report on Assessment of Compliance with Servicing Criteria for U.S. Bank Trust National Association for the period from and including January 1, ~~2014~~2015 through and including December 31, ~~2014~~2015.
34.1	Attestation Report of Ernst & Young LLP on Assessment of Compliance with Servicing Criteria relating to U.S. Bank Trust National Association.
35.1	Servicer Compliance Statement of U.S. Bank Trust National Association for the period from and including January 1, ~~2014~~2015 through and including December 31, ~~2014~~2015.

Filing Compare · STRATS (SM) Trust for Ambac Financial Group, Inc. Securities, Series 2007-1