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Exhibit 10.1

THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT

This THIRD AMENDMENT (this “Amendment”) dated as of October 31, 2018 in respect
of that certain Loan and Security Agreement dated as of September 2, 2016 (as
amended by that First Amendment dated as of September 27, 2016, as further
amended by that Second Amendment dated as of June 25, 2018 and as further
amended, supplemented or otherwise modified prior to the date hereof, the
“Credit Agreement”) by and among Cortland Capital Market Services LLC
(“Cortland”), in its capacity as administrative agent for the Lenders and
collateral agent for the Secured Parties (together with its successors and
assigns in such capacity, “Agent”), OCM Strategic Credit SIGTEC Holdings, LLC,
in its capacity as a Lender and in its capacity as Sole Lead Arranger, together
with the other Lenders from time to time party thereto (each a “Lender” and
collectively, “Lenders”), and SIGA Technologies, Inc., a Delaware corporation
(“Borrower”). Capitalized terms used and not otherwise defined herein have the
meanings assigned to them in the Credit Agreement.

WHEREAS, this Amendment includes an amendment to the Credit Agreement that has
been requested by the Loan Parties, to which Agent and the Lenders have agreed,
and that will become effective on the Third Amendment Effective Date (as defined
below) on the terms and subject to the conditions set forth herein.

Accordingly, in consideration of the foregoing, subject to the conditions set
forth herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

SECTION 1
AMENDMENTS TO THE CREDIT AGREEMENT

1.1          Amendments to Credit Agreement. The Credit Agreement is amended as
follows:

(a)          The following defined term contained in Section 11 of the Credit
Agreement is hereby amended and restated in its entirety to read in full as
follows:

““Permitted Dispositions” means (a) sales of inventory in the ordinary course of
business, (b) dispositions, in the ordinary course of business, of equipment
that is worn out, damaged or no longer used or useful in the business of a Loan
Party for cash so long as no Default or Event of Default has occurred and is
continuing at the time of such disposition or would result after giving effect
thereto, (c) the use of cash and Cash Equivalents (i) to make required payments
in connection with the PharmAthene Judgment and (ii) otherwise to the extent not
prohibited under any Loan Document, (d) dispositions not otherwise permitted
hereunder that are made for fair market value and with respect to any assets or
property not related to or subject to any contract with BARDA; provided that (i)
at the time of any such disposition, no Default or Event of Default shall exist
or shall result from such disposition, (ii) not less than 75% of the aggregate
sales price from such disposition shall be paid in cash, and (iii) the aggregate
fair market value of all assets or property so disposed of by the Loan Parties
and their Subsidiaries shall not exceed $250,000 in any calendar year; provided,
further, for the avoidance of doubt, the foregoing clause (d) shall not be
utilized to make dispositions that are permitted and governed by clause (e)
below, (e) dispositions not otherwise permitted hereunder that are made for fair
market value and with respect to assets or property subject to or related to any
contract with BARDA; provided that (i) at the time of any such disposition, no
Default or Event of Default shall exist or shall result from

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such disposition, (ii) not less than 75% of the aggregate sales price from such
disposition shall be paid in cash, and (iii) the aggregate fair market value of
all assets or property so disposed of by the Loan Parties and their Subsidiaries
shall not exceed $100,000 in any calendar year; provided, further, for the
avoidance of doubt, the foregoing clause (e) shall not be utilized to make
dispositions that are permitted and governed by clause (d) above, (f) discounts
or forgiveness of accounts receivable in the ordinary course of business or in
connection with collection or compromise thereof so long as no Default or Event
of Default has occurred and is continuing at the time of such discount or
forgiveness, or would result after giving effect thereto, and which in the
aggregate for this clause (f) shall not exceed $250,000 in the aggregate in any
calendar year, (g) licenses permitted under this Agreement, (h) issuances of
Stock or Stock Equivalents to qualifying directors (in each case, other than
Disqualified Stock), (i) Transfers among Loan Parties, (j) transactions
permitted under Sections 7.5 and 7.6, and (k) disposition of the Priority Review
Voucher granted by the FDA to Borrower in connection with the FDA’s approval of
TPOXX on July 13, 2018 (the “PRV Disposition”); provided that (i) at the time of
such disposition, no Default or Event of Default shall exist or shall result
from such disposition, (ii) not less than 75% of the aggregate sales price from
such disposition shall be paid in cash, (iii) all Net Cash Proceeds from such
disposition shall be deposited into the PRV Proceeds Account and (iv) such
disposition has occurred on or prior to December 31, 2018 (or such later date as
approved by the Requisite Lenders in their sole discretion).”
 
(b)          The following defined terms are hereby added to Section 11 of the
Credit Agreement in appropriate alphabetical order:

““Net Cash Proceeds” means the aggregate proceeds paid in cash or Cash
Equivalents received by Borrower in connection with the PRV Disposition, net of
(a) attorneys’ fees, accountants’ fees, fees paid to financial advisors, sale
commissions and related search and recording charges, transfer taxes, and other
customary fees and expenses actually incurred in connection therewith and
directly attributable thereto, (b) taxes paid or payable as a result thereof,
and (c) the amount of any reasonable reserve established in accordance with GAAP
against any adjustment to the sale price or any liabilities (other than any
taxes deducted pursuant to clause (b) above) (i) related to the PRV Disposition
and (ii) retained by the Borrower including against any indemnification
obligations (provided, however, the amount of any subsequent reduction of such
reserve (other than in connection with a payment in respect of any such
liability) shall be deemed to be Net Cash Proceeds from and after the date of
such reduction).

“PRV Disposition” has the meaning set forth in the defined term “Permitted
Dispositions.”

“PRV Proceeds Account” means a Deposit Account maintained by Borrower for the
deposit of Net Cash Proceeds from the PRV Disposition, which Deposit Account
shall at all times be subject to a Blocked Account Control Agreement.

(c)          Section 2.4(a) of the Credit Agreement is hereby amended and
restated in its entirety to read in full as follows:

“(a)      Interest Payments. For each Term Loan, Borrower shall pay interest to
Agent, for the benefit of Lenders in accordance with their Pro Rata Shares, at
the rate of interest for such Loan determined in accordance with Section 2.3 in
arrears (i) on the Escrow Release

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Date for accrued and unpaid interest from and including September 30, 2016 to
such date and (ii) thereafter, on each Scheduled Payment Date, commencing on the
first Scheduled Payment Date following the Escrow Release Date. Interest
payments due hereunder shall first, be funded from funds held in the Interest
Reserve Account, until the balance in the Interest Reserve Account is zero and
second, be funded from funds held in the PRV Proceeds Account, until the balance
in the PRV Proceeds Account is zero. On the Escrow Release Date, accrued and
unpaid interest shall be paid in accordance with Section 2.2(b)(i) and on each
Scheduled Payment Date thereafter, Agent shall automatically debit first, the
Interest Reserve Account and then, the PRV Proceeds Account for the amount of
interest then due and owing. If on any Scheduled Payment Date, there are
insufficient funds in the Interest Reserve Account or the PRV Proceeds Account,
as applicable, to fund the interest payment (or any portion thereof) then due
and owing, Borrower shall make such interest payment (or any portion thereof) by
wire transfer to the Agent Account before 2:00 p.m. (New York time) on the date
when due.”
 
(d)          Section 2.4 of the Credit Agreement is hereby amended to add the
following clause (f).

“Any voluntary prepayment or repayment of the Term Loan (including, for purposes
of clarity, a repayment of the Term Loan in full on the Final Maturity Date
pursuant to clause (y) of such defined term) may be funded from funds held in
the PRV Proceeds Account, until the balance in the PRV Proceeds Account is zero;
provided, for the avoidance of doubt, any other prepayment or repayment of the
Term Loan required under this Agreement (whether as a result of the occurrence
of the Final Maturity Date (other than pursuant to clause (y) of such defined
term), an Event of Default, acceleration of the Obligations pursuant to Section
8.2, or otherwise) shall not be funded from funds held in the PRV Proceeds
Account.”

Section 5.6(c) of the Credit Agreement is hereby amended and restated in its
entirety to read in full as follows:

“(c)        No Loan Party has any Deposit Accounts, Securities Accounts,
commodity accounts or other investment accounts other than the Escrow Account,
the Interest Reserve Account, the PRV Proceeds Account, those accounts as of the
date hereof and described in Schedule 5.6 hereto as of the date hereof, and
accounts for which the Loan Parties have delivered written notice thereof to
Agent as required pursuant to Section 6.10(d).”

(e)          Section 6.10(b) of the Credit Agreement is hereby amended and
restated in its entirety to read in full as follows:

“(b)        (i) On and after the Escrow Release Date, Borrower shall hold the
Interest Reserve in a Deposit Account and (ii) after the Escrow Release Date,
Borrower shall hold the Net Cash Proceeds from the PRV Disposition in a Deposit
Account, which, in the cases of each such Deposit Account shall be subject to a
deposit account control agreement, in form and substance reasonably satisfactory
to the Agent and Requisite Lenders and that shall provide for the Agent to have
sole dominion and control over the Interest Reserve Account and the PRV Proceeds
Account, as applicable, at all times pursuant to the terms of such deposit
account control agreement (each, a “Blocked Account Control Agreement”).
 

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(f)          Section 6.10(c) of the Credit Agreement is hereby amended and
restated in its entirety to read in full as follows:

“(c)       Other than amounts on deposit in the Interest Reserve Account or the
PRV Proceeds Account, each Loan Party shall hold all of its other cash and Cash
Equivalents in a Deposit Account or Securities Account, and each Loan Party
shall enter into, and cause each depository or securities intermediary to enter
into (x) on or before the Escrow Release Date, for any such Deposit Accounts or
Securities Accounts (other than an Excluded Account) opened or maintained as of
the Escrow Release Date or (y) prior to or concurrently with the establishment
or acquisition of any new Deposit Account or Securities Account (other than an
Excluded Account) established or acquired after the Escrow Release Date, in each
case, in form and substance reasonably satisfactory to Agent and Requisite
Lenders (together with any Blocked Account Control Agreement, each an “Account
Control Agreement”) with respect to each such Deposit Account and Securities
Account maintained by such Person. All such Account Control Agreements (other
than with respect to any Blocked Account Control Agreement) shall provide for
“springing” cash dominion with respect to each such account, including each
disbursement account. With respect to each Account Control Agreement providing
for “springing” cash dominion, Agent will not deliver to the relevant depository
institution a notice or other instruction which provides for exclusive control
over such account by Agent until an Event of Default has occurred and is
continuing.”

SECTION 2
REPRESENTATIONS AND WARRANTIES

2.1         Representations and Warranties. To induce Agent and Lenders to enter
into this Amendment, each Loan Party represents and warrants, on and as of the
Third Amendment Effective Date, that the following statements are true and
correct on and as of the Third Amendment Effective Date:

(a)         The execution, delivery and performance by each Loan Party of this
Amendment will not (a) contravene any of the organizational documents of such
Loan Party, (b) violate any material Requirement of Law, (c) require any action
by, filing, registration, qualification with, or approval, consent or
withholding of objections from, any Governmental Authority or any other Person,
except those which have been obtained and are in full force and effect, (d)
result in the creation of any Lien on any of such Loan Party’s Property (except
for Liens in favor of Agent, on behalf of itself and the other Secured Parties),
or (e) result in any breach of or constitute a default under, or permit the
termination or acceleration of, any Material Agreement to which such Loan Party
is a party.

(b)         This Amendment has been duly authorized, executed and delivered by
each Loan Party and constitutes the legal, valid and binding obligations of each
such Person that is a party hereto, enforceable against such Person in
accordance with its terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, or similar laws affecting the enforcement of creditors’
rights generally or by equitable principles relating to enforceability.

(c)         The representations and warranties of each Loan Party contained in
Section 5 of the Credit Agreement or any other Loan Document are true and
correct in all material respects (or with respect to such representations and
warranties which by their terms contain materiality qualifiers, shall be true
and correct) in each case on and as of the Third Amendment Effective Date,
except to the extent that such representations and warranties specifically refer
to an earlier date, in which case they shall be true and correct in all material
respects (or with respect to such representations and warranties which by their
terms contain materiality qualifiers, shall be true and correct) as of such
earlier date.
 

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SECTION 3
CONDITIONS TO EFFECTIVENESS

3.1        Third Amendment Effective Date. This Amendment shall become effective
as of the first date (the “Third Amendment Effective Date”) on which each of the
following conditions shall have been satisfied:

(a)          Execution and Delivery of this Amendment. Agent and Lenders shall
have received a counterpart signature page of this Amendment duly executed by
each of the Loan Parties.

(b)         Representations and Warranties. The representations and warranties
set forth in Section 2.1 shall be true and correct on the Third Amendment
Effective Date.

SECTION 4
POST-CLOSING CONDITIONS

4.1          Post-Closing Conditions.

(a)        Within four (4) Business Days of the Third Amendment Effective Date,
Borrower shall file an 8-K, in form and substance reasonably acceptable to the
Agent and Lenders, disclosing this Amendment and transactions described herein;
provided that any 8-K that attaches the Third Amendment as an exhibit shall be
deemed reasonably acceptable. Notwithstanding any provision of this Amendment or
any other Loan Document, the Borrower’s failure to perform or observe this
post-closing condition shall constitute an immediate Event of Default under the
Loan Agreement.
   

(b)         By November 14, 2018 (or such longer date as Agent (at the direction
of the Requisite Lenders in their sole discretion) may permit), Borrower shall
have either (i) caused Signature Bank to provide to Agent internet banking view
only access to that certain Deposit Account (as defined in that certain Control
Account Agreement, effective as of October 24, 2018, by and among Borrower,
Agent and Signature Bank) or (ii) moved such Deposit Account to another bank and
caused such bank to enter into an Account Control Agreement.  Notwithstanding
any provision of this Amendment or any other Loan Document, the Borrower’s
failure to perform or observe this post-closing condition shall constitute an
immediate Event of Default under the Loan Agreement.

SECTION 5
REAFFIRMATION

5.1         Reaffirmation. Borrower hereby ratifies and reaffirms all of its
payment and performance obligations, contingent or otherwise, under each of the
Loan Documents to which it is a party (after giving effect hereto). Borrower
acknowledges that each of the Loan Documents remains in full force and effect
and is hereby ratified and reaffirmed. The execution of this Amendment shall not
operate as a waiver of any right, power or remedy of Agent or Lenders,
constitute a waiver of any provision of any of the Loan Documents or serve to
effect a novation of the Obligations.

SECTION 6
MISCELLANEOUS

6.1        Governing Law. THIS AMENDMENT AND ANY CLAIMS, CONTROVERSY, DISPUTE OR
CAUSE OF ACTION (WHETHER IN CONTRACT OR TORT OR OTHERWISE) BASED UPON, ARISING
OUT OF OR RELATING TO THIS AMENDMENT AND THE TRANSACTIONS CONTEMPLATED HEREBY
SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF
NEW YORK (WITHOUT REGARD TO THE CONFLICT OF LAWS PRINCIPLES OF SUCH STATE).

6.2          Successors and Assigns. The provisions of this Amendment shall be
binding upon and inure to the benefit of the parties hereto and their respective
successors and permitted assigns; provided that none of the Loan Parties may
assign or transfer any of its rights or obligations under this Amendment except
as permitted by the Credit Agreement.

6.3          Counterparts; Effectiveness. This Amendment may be executed in any
number of counterparts, each of which counterparts, when so executed and
delivered, shall be deemed to be an

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original and all of which counterparts, taken together, shall constitute but one
and the same Amendment. Faxed or otherwise electronically submitted signatures
to this Amendment shall be binding for all purposes. 

6.4         Severability. Any provision of this Amendment being held illegal,
invalid or unenforceable in any jurisdiction shall not affect any part of such
provision not held illegal, invalid or unenforceable, any other provision of
this Amendment or any part of such provision in any other jurisdiction.

6.5          Effects of this Amendment.

(a)         Except as expressly set forth herein, this Amendment shall not by
implication or otherwise limit, impair, constitute a waiver of or otherwise
affect the rights and remedies of Agent or the Lenders under the existing Credit
Agreement or any other Loan Document, and shall not alter, modify, amend or in
any way affect any of the terms, conditions, obligations, covenants or
agreements contained in the Credit Agreement or any other provision of the
Credit Agreement or of any other Loan Documents, all of which are ratified and
affirmed in all respects and shall continue in full force and effect.

(b)        From and after the Third Amendment Effective Date, each reference in
the Credit Agreement to “this Agreement”, “hereunder”, “hereof”, “herein”, or
words of like import, and each reference to the Credit Agreement in any other
Loan Document shall be deemed a reference to the Credit Agreement as amended
hereby. This Amendment shall constitute a “Loan Document” for all purposes of
the Credit Agreement and the other Loan Documents.

6.6         Release. In consideration of the Lenders’ and Agent’s agreements
contained in this Amendment, each Loan Party hereby irrevocably releases and
forever discharge the Lenders and the Agent and their affiliates, subsidiaries,
successors, assigns, directors, officers, employees, agents, consultants and
attorneys (each, a “Released Person”) of and from any and all claims, suits,
actions, investigations, proceedings or demands, whether based in contract,
tort, implied or express warranty, strict liability, criminal or civil statute
or common law of any kind or character, known or unknown, which such Loan Party
ever had or now has against Agent, any Lender or any other Released Person which
relates, directly or indirectly, to any acts or omissions of Agent, any Lender
or any other Released Person relating to the Credit Agreement or any other Loan
Document on or prior to the date hereof.

[Signature Pages Follow]
 

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IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of
the date set forth above.

 
BORROWER:
       
SIGA TECHNOLOGIES, INC.
         
By:
/s/ Daniel J. Luckshire
   
Name:
Daniel J. Luckshire    
Title:
Chief Financial Officer
 

[Signature Page to Third Amendment to Loan and Security Agreement]
 

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AGENT:
       
CORTLAND CAPITAL MARKET SERVICES LLC
         
By:
/s/ Matthew Trybula
   
Name:
Matthew Trybula    
Title:
Associate Counsel
 

[Signature Page to Third Amendment to Loan and Security Agreement]
 

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LENDER:
       
OCM STRATEGIC CREDIT SIGTEC HOLDINGS, LLC
       
By: Oaktree Fund GP IIA, LLC
 
Its: Manager
 
By: Oaktree Fund GP II, L.P.
 
Its: Managing Member
         
By:
/s/ Nilay Mehta
   
Name:
Nilay Mehta    
Title:
Senior Vice President
           
By:
/s/ Edgar Lee
   
Name:
Edgar Lee    
Title:
Managing Director
 

[Signature Page to Third Amendment to Loan and Security Agreement]

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