UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13D Under the Securities Exchange Act of 1934 (Amendment No. 5)(1) NETWORK - 1 SECURITY SOLUTIONS, INC. (Name of Issuer) Common Stock, $0.01 Par Value Per Share (Title of Class of Securities) 64121N109 (CUSIP Number) Wheatley Partners II, L.P. 80 Cuttermill Road Great Neck, NY 11021 Telephone: (516) 773-1024 With a copy to: Morrison Cohen Singer & Weinstein, LLP 750 Lexington Avenue New York, NY 10022 Telephone: (212) 735-8600 (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) April 13, 2004 (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of ss.ss.240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. |_| Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See 13d-7(b) for other parties to whom copies are to be sent. (Continued on following page(s)) (1) 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 disclosures provided in a prior cover page. The information required on 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). 1 of 24 CUSIP No. 64121N109 13D Page 2 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Wheatley Partners II, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 1,430,507 shares 9.5% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 1,430,507 shares 9.5% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,430,507 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 9.5% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 3 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Irwin Lieber - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 700,064 shares 4.6% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 1,666,355 shares 11.1% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 700,064 shares 4.6% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 1,666,355 shares 11.1% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,366,419 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 15.7% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 4 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Barry Rubenstein - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 248,509 shares 1.6% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 4,095,644 shares 26.6% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 248,509 shares 1.6% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 4,095,644 shares 26.6% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,344,153 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 28.1% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 5 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Barry Fingerhut - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 610,660 shares 4.0% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 1,666,355 shares 11.1% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 610,660 shares 4.0% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 1,666,355 shares 11.1% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,277,015 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 15.1% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 6 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Seth Lieber - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 34,136 shares 0.2% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 1,796,518 shares 11.9% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 34,136 shares 0.2% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 1,796,518 shares 11.9% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,830,654 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 12.2% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 7 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Jonathan Lieber - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 32,584 shares 0.2% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 1,796,518 shares 11.9% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 32,584 shares 0.2% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 1,796,518 shares 11.9% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,829,102 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 12.2% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 8 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Woodland Venture Fund - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 1,016,064 shares 6.7% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 1,016,064 shares 6.7% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,016,064 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 6.7% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 19 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Seneca Ventures - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 713,400 shares 4.7% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 713,400 shares 4.7% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 713,400 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 4.7% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 10 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Marilyn Rubenstein - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* PF, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 2,382 shares 0.02% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 2,426,907 shares 15.8% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 2,382 shares 0.02% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 2,426,907 shares 15.8% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,429,289 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 15.8% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* IN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 11 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Woodland Services Corp. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 0 shares 0% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 1,729,364 shares 11.3% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 0 shares 0% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 1,729,364 shares 11.3% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,729,364 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 11.3% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* CO - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 12 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Woodland Partners - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 402,733 shares 2.7% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 402,733 shares 2.7% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 402,733 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.7% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 13 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Brookwood Partners, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 294,810 shares 2.0% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 294,810 shares 2.0% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 294,810 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 2.0% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 14 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Applegreen Partners - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION New York - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 130,163 shares 0.9% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 0 shares 0% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 130,163 shares 0.9% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 0 shares 0% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 130,163 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0.9% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 15 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Wheatley Partners, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 216,980 shares 1.4% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 18,868 shares 0.1% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 216,980 shares 1.4% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 18,868 shares 0.1% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 235,848 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.5% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 16 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Wheatley Foreign Partners, L.P. - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* WC, OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 18,868 shares 0.1% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 216,980 shares 1.4% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 18,868 shares 0.1% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 216,980 shares 1.4% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 235,848 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.5% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* PN - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 17 of 24 Pages - -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSON Wheatley Partners, LLC - -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) |_| (b) |_| - -------------------------------------------------------------------------------- 3 SEC USE ONLY - -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* OO - -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) |_| - -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware - -------------------------------------------------------------------------------- 7 SOLE VOTING POWER 0 shares 0% ----------------------------------------------------------------- NUMBER OF 8 SHARED VOTING POWER SHARES BENEFICIALLY 235,848 shares 1.5% OWNED BY ----------------------------------------------------------------- EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON 0 shares 0% WITH ----------------------------------------------------------------- 10 SHARED DISPOSITIVE POWER 235,848 shares 1.5% - -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 235,848 shares - -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* |_| - -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.5% - -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON* OO - -------------------------------------------------------------------------------- *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 64121N109 13D Page 18 of 24 Pages This statement, dated April 13, 2004, constitutes Amendment No. 5 to the Schedule 13D, dated November 12, 1998, regarding the reporting persons' ownership of certain securities of Network-1 Security Solutions, Inc. All capitalized terms used herein and otherwise undefined shall have the meanings ascribed in the Schedule. ITEM 3. Source and Amount of Funds or Other Consideration. Item 3 is hereby amended as follows: On April 13, 2004, pursuant to the provisions of an exchange agreement with the Issuer, each of Wheatley Partners II, L.P., Wheatley Partners, L.P., Wheatley Foreign Partners, L.P., Barry Rubenstein, Irwin Lieber, Barry Fingerhut, Seth Lieber, Jonathan Lieber, Woodland Venture Fund, Seneca Ventures, Woodland Partners, Brookwood Partners, L.P., Applegreen Partners and Marilyn Rubenstein exchanged the number of shares of Series D Preferred Stock and/or Series E Preferred Stock reflected in Item 5(c) below for shares of Common Stock of the Issuer. Holders of the Series D Preferred Stock and the Series E Preferred Stock received 1.25 shares of Common Stock for each share of Common Stock such holder would have received based upon the prior conversion rates for each share of preferred stock. ITEM 5. Interests in Securities of the Issuer. Item 5 is hereby amended and restated as follows: (a) The following list sets forth the aggregate number and percentage (based on 15,012,576 shares of Common Stock outstanding as reported in the Issuer's Form 10-KSB for the year ended December 31, 2003), of outstanding shares of Common Stock owned beneficially by each reporting person named in Item 2, as of April 13, 2004: