SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G/A
Under the Securities Exchange Act of 1934
(Amendment No. 4)*
SIGA Technologies, Inc.
(Name of Issuer)
Common Stock, $.0001 par value
(Title of Class of Securities)
826917106
(CUSIP Number)
December 31, 2016
(Date of Event Which Requires Filing of This Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
☐ | Rule 13d-1(b)
| Rule 13d-1(c)
☐ | Rule 13d-1(d)
(Page 1 of 11 Pages)

*The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 (" Act ") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 826917106 | 13G/A | Page 2  of 11 Pages

1

NAME OF REPORTING PERSON
Jet Capital Master Fund, LP

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
Cayman Islands

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 4,027,599 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 4,027,599 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
4,027,599

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
7.42%

12

TYPE OF REPORTING PERSON
PN

CUSIP No. 826917106 | 13G/A | Page 3  of 11 Pages

1

NAME OF REPORTING PERSON
Jet Capital SRM Master Fund, LP

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
State of Delaware

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 348,796 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 348,796 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
348,796

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
0.64%

12

TYPE OF REPORTING PERSON
PN

CUSIP No. 826917106 | 13G/A | Page 4  of 11 Pages

1

NAME OF REPORTING PERSON
Jet Capital Investors, L.P.

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
State of Delaware

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 5,046,891 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 5,046,891 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
5,046,891

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
9.30%

12

TYPE OF REPORTING PERSON
IA

CUSIP No. 826917106 | 13G/A | Page 5  of 11 Pages

1

NAME OF REPORTING PERSON
Jet Capital Management, L.L.C.

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
State of Delaware

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 4,376,395 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 4,376,395 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
4,376,395

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
8.06%

12

TYPE OF REPORTING PERSON
OO

 

CUSIP No. 826917106 | 13G/A | Page 6  of 11 Pages

1

NAME OF REPORTING PERSON
Alan S. Cooper

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
United States

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 5,046,891 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 5,046,891 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
5,046,891

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
9.30%

12

TYPE OF REPORTING PERSON
IN

 

CUSIP No. 826917106 | 13G/A | Page 7  of 11 Pages

1

NAME OF REPORTING PERSON
Matthew Mark

2

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

(a) ☐
(b)

3 | SEC USE ONLY |

4

CITIZENSHIP OR PLACE OF ORGANIZATION
United States

NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH:

5

SOLE VOTING POWER
0

| 6 | SHARED VOTING POWER 5,046,891 | |
| 7 | SOLE DISPOSITIVE POWER 0 | | |
| 8 | SHARED DISPOSITIVE POWER 5,046,891 | | |

9

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
5,046,891

10 | CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES | ☐ | | |

11

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
9.30%

12

TYPE OF REPORTING PERSON
IN

CUSIP No. 826917106 | 13G/A | Page 8  of 11 Pages
 
Item 1(a). | NAME OF ISSUER
| SIGA TECHNOLOGIES, INC.
 
Item 1(b). | ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
| 660 Madison Avenue, Suite 1700, New York, NY 10065.
 
Item 2(a). | NAME OF PERSON FILING

(i) Jet Capital Master Fund LP (the "Master Fund"), a Cayman Islands limited partnership, with respect to shares of Common Stock (as defined in Section 2(d)) directly held by it.
 
(ii) Jet Capital SRM Master Fund LP (the "SRM Master Fund" and together with the Master Fund, the " Master Funds "), a Delaware limited partnership, with respect to shares of Common Stock directly held by it.
 
(iii) Jet Capital Investors, L.P. (the "Investment Manager"), a Delaware limited partnership, which serves as investment manager to the Master Funds and certain discretionary accounts (the " Discretionary Accounts ", and together with the Master Funds, the " Funds ") with respect to shares of Common Stock directly held by the Funds.
 
(iv) Jet Capital Management, L.L.C. (the "General Partner"), a Delaware limited liability company, which serves as the general partner of each of the Master Funds, with respect to shares of Common Stock directly held by the Master Funds.
 
(v) Alan S. Cooper ("Mr. Cooper"), who, together with Mr. Mark, is responsible for the supervision and conduct of all investment activities of the Investment Manager, including, without limitation, for all investment decisions with respect to the assets of the Funds, with respect to shares of Common Stock directly held by the Funds.
 
(vi) Matthew Mark ("Mr. Mark"), who, together with Mr. Cooper, is responsible for the supervision and conduct of all investment activities of the Investment Manager, including, without limitation, for all investment decisions with respect to the assets of the Funds, with respect to shares of Common Stock directly held by the Funds.

| The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons."  Any disclosures herein with respect to persons other than the Reporting Persons are made on information and belief after making inquiry to the appropriate party.  The filing of this statement should not be construed as an admission that any of the Reporting Persons is, for the purposes of Section 13G of the Act, the beneficial owner of the Common Stock reported herein.
 
Item 2(b). | ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
| The address of the business office of each of the Reporting Persons is  540 Madison Avenue, 17th Floor, New York, New York 10022.

CUSIP No. 826917106 | 13G/A | Page 9  of 11 Pages
 
Item 2(c). | CITIZENSHIP
| The Master Fund is a Cayman Islands limited partnership. The SRM Master Fund is a Delaware limited partnership. The Investment Manager is a Delaware limited partnership. The General Partner is a Delaware limited liability company. Messrs. Cooper and Mark are citizens of the United States.
 
Item 2(d). | TITLE OF CLASS OF SECURITIES
| Common Stock, $.0001 par value (the "Common Stock")
 
Item 2(e). | CUSIP NUMBER
| 826917106
 
Item 3. | IF THIS STATEMENT IS FILED PURSUANT TO Rules 13d-1(b), OR 13d-2(b) OR (c), CHECK WHETHER THE PERSON FILING IS A:
 
| (a) | ☐ | Broker or dealer registered under Section 15 of the Act;
| (b) | ☐ | Bank as defined in Section 3(a)(6) of the Act;
| (c) | ☐ | Insurance company as defined in Section 3(a)(19) of the Act;
| (d) | ☐ | Investment company registered under Section 8 of the Investment Company Act of 1940;
| (e) | ☐ | An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E);
| (f) | ☐ | An employee benefit plan or endowment fund in accordance with Rule 13d-1(b)(1)(ii)(F);
| (g) | ☐ | A parent holding company or control person in accordance with Rule 13d-1(b)(1)(ii)(G);
| (h) | ☐ | A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act;
| (i) | ☐ | A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act;
| (j) | ☐ | A non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J);
| (k) | ☐ | Group, in accordance with Rule 13d-1(b)(1)(ii)(K).

If filing as a non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J), please
specify the type of institution: ____________________________________________

 

CUSIP No. 826917106 | 13G/A | Page 10  of 11 Pages
 
Item 4. | OWNERSHIP
| The information required by Items 4(a)-(c) is set forth in rows 5-11 for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
| The percentage in this Schedule 13G/A are calculated based upon 54,284,296 shares of Common Stock outstanding as of October 31, 2016, as reflected in SIGA Technologies, Inc.'s Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2016 filed with the Securities and Exchange Commission on November 2, 2016.
 
Item 5. | OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
| Not applicable.
 
Item 6. | OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
| Not applicable.
 
Item 7. | IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY OR CONTROL PERSON
| Not applicable.
 
Item 8. | IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
| Not applicable.
 
Item 9. | NOTICE OF DISSOLUTION OF GROUP
| Not applicable.
 
Item 10. | CERTIFICATION
 
| Each of the Reporting Persons hereby makes the following certification:
| By signing below each Reporting Person certifies that, to the best of his or its knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

CUSIP No. 826917106 | 13G/A | Page 11  of 11 Pages
 
SIGNATURES
After reasonable inquiry and to the best of his or its knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.
DATE: February 14, 2017
 
JET CAPITAL MASTER FUND, LP |
By: | Jet Capital Management, L.L.C. |
By: | /s/ Matthew Mark |
Name:	Matthew Mark |
Title:	Managing Member |
JET CAPITAL SRM MASTER  FUND, LP |
By: | Jet Capital Management, L.L.C. |
By: | /s/ Matthew Mark |
Name:	Matthew Mark |
Title:	Managing Member |
Jet Capital Investors, L.P. |
By: | Jet Capital G.P. L.L.C. |
By: | /s/ Matthew Mark |
Name:	Matthew Mark |
Title:	Managing Member |
Jet Capital Management, L.L.C. |
By: | /s/ Matthew Mark |
Name:	Matthew Mark |
Title:	Managing Member |
/s/ Alan S. Cooper |
Alan s. Cooper, individually |
/s/ Matthew Mark |
Matthew mark, individually |