SIGA TECHNOLOGIES INC — Director's Dealing 2009

May 1, 2009

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: SIGA TECHNOLOGIES INC (SIGA)
CIK: 0001010086
Period of Report: 2009-04-29

Reporting Person: PERELMAN RONALD O (10% Owner)
Reporting Person: MacAndrews & Forbes LLC (10% Owner)
Reporting Person: MacAndrews & Forbes Holdings Inc. (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2009-04-30	Common Stock, par value $.0001 per share	X	490196	$3.06	Acquired	4635235	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2009-04-29	Equity Line	$	X	1	Acquired	2010-06-19	Common Stock and Warrants ()	Indirect
2009-04-30	Warrant (Right to Buy)	$3.519	X	196078	Acquired	2009-04-30	Common Stock (196078)	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock, par value $.0001 per share	3472222	Indirect

Footnotes

F1: The shares were issued in consideration for an investment of $1,500,000 by MacAndrews & Forbes LLC ("MacAndrews & Forbes") in SIGA Technologies, Inc. (the "Company"), pursuant to the Letter Agreement (as defined in footnote 2), as amended by the Extension Agreement (as defined in footnote 3).

F2: On June 19, 2008, MacAndrews & Forbes entered into a letter agreement (the "Letter Agreement") with the Company that provided that for a period of one year, (i) MacAndrews & Forbes committed to invest, at the Company's option, up to an aggregate of $8,000,000 in up to three tranches (such commitment, the "Investment Commitment") and (ii) MacAndrews & Forbes may have, at MacAndrews & Forbes' option, elected to invest up to $8,000,000 in the Company in up to three tranches on the terms of the Investment Commitment (such option, the "Investment Option"); provided that in no event could the aggregate amount of the investments pursuant to the Investment Commitment and the Investment Option exceed $8,000,000.

F3: On April 29, 2009, the Company and MacAndrews & Forbes entered into a letter agreement (the "Extension Agreement") extending the term of the commitments under the Letter Agreement through June 19, 2010, and increasing the number of tranches available from no more than three to no more than six. The remaining terms of the Letter Agreement remain unchanged.

F4: Upon either of the Company's election to effect an investment pursuant to the Investment Commitment or MacAndrews & Forbes' election to effect an investment pursuant to the Investment Option (each, an "Investment") the Company shall issue to MacAndrews & Forbes: (i) such number of shares of Common Stock, with a value equal to the Investment, at a per share valuation ("Per Share Price") equal to the lesser of (A) $3.06 and (B) the average of the volume-weighted average price per share for the 5 trading days immediately preceding each funding date and (ii) warrants (the "Consideration Warrants"), for no additional consideration, to purchase a number of shares of Common Stock of the Company equal to 40% of the shares issued on such funding date, at an exercise price per share equal to 115% of the Per Share Price on such funding date, payable in cash or by cashless exercise, exercisable for a period of four years commencing on the date of issuance of such Consideration Warrants.

F5: To the extent that the consummation of any portion of the transactions contemplated by the Letter Agreement would require shareholder approval under applicable Nasdaq rules, the Company shall be obligated to consummate only that portion of the transaction that will not require such shareholder approval. The consummation of Investment transactions contemplated by the Letter Agreement is subject to the negotiation, execution and delivery of definitive documentation.

F6: On April 30, 2009, MacAndrews & Forbes funded $1,500,000 to the Company pursuant to the terms of the Letter Agreement, as amended by the Extension Agreement. As a result of this transaction, $6,500,000 of the Investment Commitment / Investment Option remains outstanding.

F7: The warrants were issued as Consideration Warrants in connection with the investment described in footnote 6 under the terms of the Letter Agreement, as amended by the Extension Agreement.