FORM 4 -------------------------- OMB APPROVAL -------------------------- OMB Number.......3235-0287 Expires: December 31, 2001 Estimated average burden hours per response.....0.5 -------------------------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(f) of the Investment Company Actof 1940 [_] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instructions 1(b). -------------------------------------------------------------------------------- 1. Name and Address of Reporting Person Cerrone, Gabriel M. 265 East 66th Street, Suite 16G New York New York 10021 -------------------------------------------------------------------------------- 2. Issuer Name and Ticker or Trading Symbol Siga Technologies, Inc. ("SIGA") -------------------------------------------------------------------------------- 3. IRS or Social Security Number of Reporting Person (Voluntary) -------------------------------------------------------------------------------- 4. Statement for Month/Year SEPTEMBER 2001 -------------------------------------------------------------------------------- 5. If Amendment, Date of Original (Month/Year) -------------------------------------------------------------------------------- 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) [x] Director [x] 10% Owner [_] Officer (give title below) [_] Other (specify below) -------------------------------------------------------------------------------- 7. Individual or Joint/Group Filing (Check Applicable Line) [x] Form filed by One Reporting Person [_] Form filed by More than One Reporting Person ----------------------------------------------------------------------------------------------------------------------------------- Table I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned | -----------------------------------------------------------------------------------------------------------------------------------| 1. Title of Security |2. |3. |4.Securities Acquired (A) |5.Amount of |6.Dir |7.Nature of Indirect | | Transaction | or Disposed of (D) | Securities |ect | Beneficial Ownership | | | | | Beneficially |(D)or | | | | | | | A/| | Owned at |Indir | | | Date |Code|V| Amount | D | Price | End of Month |ect(I)| | -----------------------------------------------------------------------------------------------------------------------------------| -----------------------------------------------------------------------------------------------------------------------------------| Common Stock |09/19/01| P | | 19,584 | A | (1) | 1,926,972(2) | I(3) |By Panetta Partners Ltd.(4) | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. * If the form is filed by more than one reporting person, see Instruction 5(b)(v). (Over) SEC 1474 (7-96) Page 1 of 2 ----------------------------------------------------------------------------------------------------------------------------------- Table II -- Derivative Securitites Acquired, Disposed of, or Beneficially Owned | -----------------------------------------------------------------------------------------------------------------------------------| 1.Title of |2.Con- |3. |4. |5.Number of De |6.Date Exer |7.Title and Amount |8.Price|9.Number |10.|11.Nature | Derivative |version |Transaction | rivative Secu |cisable and | of Underlying |of Deri|of Deriva |Dir|of In- | Security |or Exer | | | rities Acqui |Expiration | Securities |vative |tive |ect|direct | |cise | | | red(A) or Dis |Date(Month/ | |Secu |Securities |(D)|Beneficial| |Price of| | | posed of(D) |Day/Year) | |rity |Benefi |or |Ownership | |Deriva- | | | |Date |Expir | | |ficially |Ind| | |tive | | | | A/|Exer- |ation | Title and Number| |Owned at |ire| | |Secu- | | | | | D |cisa- |Date | of Shares | |End of |ct | | |rity |Date |Code|V| Amount | |ble | | | |Month |(I)| | -----------------------------------------------------------------------------------------------------------------------------------| -----------------------------------------------------------------------------------------------------------------------------------| Stock Option | | | | | | | | | Common | | | | | | (Right to buy) | $2.50 |08/15/01| A |V| 1,075,000 | |08/15/01| 05/03/11| Stock |1,075,000| |1,075,000 | D | | -----------------------------------------------------------------------------------------------------------------------------------| Warrant | | | | | | | | | Common | | | | |By Panetta| (Right to buy) | $3.552 |09/19/01| P | | 14,688 | | (5) | 09/19/08| Stock | 14,688| | 14,688 | I | (4) | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| | | | | | | | | | | | | | | | -----------------------------------------------------------------------------------------------------------------------------------| Explanation of Responses: 1. Panetta purchased 19,584 shares of Common Stock and Warrants to purchase up to 14,688 shares of Common Stock for an aggregate purchase price of $60,000. 2. Includes 649,388 shares of Common Stock issuable upon exercise of Warrants that Mr. Cerrone does not currently have the right to exercise. See Attachment A. 3. Mr. Cerrone may be deemed beneficially to own 1,075,000 of the shares of Common Stock included in column 5 directly in his own name (issuable upon exercise of stock options) and the rest indirectly through Panetta. 4. Panetta Partners Ltd., a limited partnership of which Mr. Cerrone is the sole general partner, is the direct owner of these securities which Mr. Cerrone may be deemed to beneficially own. 5. See Attachment A. /s/ Gabriel M. Cerrone -------------------------------- ** Signature of Reporting Person October 10, 2001 ------------------------ Date ** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a). Note: File three copies of this Form, one of which must be manually signed. If space provided is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number. SEC 1474 (7-96) Page 2 of 2 ATTACHMENT A Reporting Person: Gabriel M. Cerrone Issuer: SIGA Technologies, Inc. (SIGA) Report: Form 4 for September 2001 The Reporting Person holds warrants that each provide that, with certain limited exceptions, it is not exercisable, if as a result of such exercise, the number of shares of Common Stock beneficially owned by the Reporting Person and his affiliates (other than shares of Common Stock which may be deemed beneficially owned through the ownership of the unexercised portion of such warrants) would exceed 9.99% of the outstanding shares of Common Stock. As a result of such restrictions and other securities which the Reporting Person may be deemed beneficially to own as of September 30, 2001, the Reporting Person's warrants are not presently exercisable. Nonetheless, the Reporting Person may be deemed to have a pecuniary interest in such warrants and in the Common Stock issuable upon exercise thereof.