UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 S C H E D U L E 13D Under the Securities Exchange Act of 1934 (Amendment No. 3)(1) NETWORK-1 SECURITY SOLUTIONS, INC. (Name of Issuer) COMMON STOCK, $0.01 PAR VALUE (Title of Class of Securities) 64121N109 (CUSIP Number) Copy to: Michael R. Reiner, Esq. Wheatley Partners II, L.P. Morrison Cohen Singer & Weinstein, LLP 80 Cuttermill Road 750 Lexington Avenue Great Neck, NY 11021 New York, New York 10022 Telephone (516) 773-1024 Telephone (212) 735-8600 (Name, Address and Telephone Number of Persons Authorized to Receive Notices and Communications) October 2, 2001 (Date of Event which Requires Filing 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 Rule 13d-1(e), 13d- 1(f) or 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 Rule 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). Page 1 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification Nos. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 1,572,015 shares 23.0% Shares ---------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each ---------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 1,572,015 shares 23.0% With ---------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 1,572,015 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 23.0% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 2 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) Applewood Capital Corp. - -------------------------------------------------------------------------------- 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 0 shares 0% Shares ---------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each ---------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 0 shares 0% With ---------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 0 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% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* CO ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 3 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 933,011 shares 12.6% Shares ------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 1,949,371 shares 27.0% Each ------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 933,011 shares 12.6% With ------------------------------------------------------------- 10 Shared Dispositive Power 1,949,371 shares 27.0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 2,882,382 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 35.4% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 4 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 319,056 shares 4.7% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 5,204,209 shares 51.1% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 319,056 shares 4.7% With -------------------------------------------------------------- 10 Shared Dispositive Power 5,204,209 shares 51.1% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 5,523,265 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 52.7% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 5 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 843,607 shares 11.6% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 1,949,371 shares 27.0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 843,607 shares 11.6% With -------------------------------------------------------------- 10 Shared Dispositive Power 1,949,371 shares 27.0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 2,792,978 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 34.8% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 6 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 51,824 shares 0.8% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 2,128,926 shares 28.8% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 51,824 shares 0.8% With -------------------------------------------------------------- 10 Shared Dispositive Power 2,128,926 shares 28.8% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 2,180,750 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 29.3% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 7 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 50,272 shares 0.8% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 2,128,926 shares 28.8% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 50,272 shares 0.8% With -------------------------------------------------------------- 10 Shared Dispositive Power 2,128,926 shares 28.8% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 2,179,198 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 29.3% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 8 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 1,305,071 shares 17.1% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 1,305,071 shares 17.1% With -------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 1,305,071 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 17.1% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 9 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 946,347 shares 13.0% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 946,347 shares 13.0% With -------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 946,347 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 13.0% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 10 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization United States - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 2,176 shares 0.03% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 3,252,662 shares 34.5% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 2,176 shares 0.03% With -------------------------------------------------------------- 10 Shared Dispositive Power 3,252,662 shares 34.5% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 3,254,838 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 34.5% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* IN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 11 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 0 shares 0% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 2,251,419 shares 29.5% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 0 shares 0% With -------------------------------------------------------------- 10 Shared Dispositive Power 2,251,419 shares 29.5% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 2,251,419 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 29.5% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* CO ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 12 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 529,547 shares 7.6% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 529,547 shares 7.6% With -------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 529,547 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 7.6% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 13 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 471,696 6.8% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 471,696 6.8% With -------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 471,696 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 6.8% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 14 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization New York - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 179,555 shares 2.7% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 0 shares 0% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 179,555 shares 2.7% With -------------------------------------------------------------- 10 Shared Dispositive Power 0 shares 0% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 179,555 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! Page 15 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization Delaware - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 347,168 shares 5.1% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 30,188 shares 0.5% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 347,168 shares 5.1% With -------------------------------------------------------------- 10 Shared Dispositive Power 30,188 shares 0.5% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 377,356 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 5.5% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 16 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization Delaware - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 30,188 shares 0.5% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 347,168 shares 5.1% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 30,188 shares 0.5% With -------------------------------------------------------------- 10 Shared Dispositive Power 347,168 shares 5.1% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 377,356 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 5.5% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* PN ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 17 of 33 CUSIP No. 64121N109 13D ================================================================================ 1 Names of Reporting Persons I.R.S. Identification No. of Above Persons (Entities Only) 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 Item 2(d) or 2(e) [ ] - -------------------------------------------------------------------------------- 6 Citizenship or Place of Organization Delaware - -------------------------------------------------------------------------------- 7 Sole Voting Power Number of 0 shares 0% Shares -------------------------------------------------------------- Beneficially 8 Shared Voting Power Owned By 377,356 shares 5.5% Each -------------------------------------------------------------- Reporting 9 Sole Dispositive Power Person 0 shares 0% With -------------------------------------------------------------- 10 Shared Dispositive Power 377,356 shares 5.5% - -------------------------------------------------------------------------------- 11 Aggregate Amount Beneficially Owned By Each Reporting Person 377,356 shares - -------------------------------------------------------------------------------- 12 Check Box if the Aggregate Amount in Row (11) excludes Certain Shares* [ ] - -------------------------------------------------------------------------------- 13 Percent of Class Represented by Amount in Row (11) 5.5% - -------------------------------------------------------------------------------- 14 Type of Reporting Person* OO ================================================================================ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 18 of 33 This statement, dated October 2, 2001, constitutes Amendment No. 3 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 1. Security and Issuer. Item 1 is hereby amended by adding the following paragraphs: This statement relates to the shares of common stock, $0.01 par value per share (the "Common Stock") of Network-1 Security Solutions, Inc. (the "Issuer"). The principal executive offices of the Issuer are located at 1601 Trapelo Road, Reservoir Place, Waltham, Massachusetts 02451. ITEM 2. Identity and Background. Item 2 is hereby amended by adding the following paragraphs: Items 2(a), 2(b), 2(c) and 2(f). This Statement is jointly filed by the following entities (collectively referred to as the "Reporting Persons"): o Wheatley Partners, L.P., a Delaware limited partnership ("Wheatley"); o Wheatley Foreign Partners, L.P., a Delaware limited partnership ("Wheatley Foreign"); o Wheatley Partners II, L.P., a New York limited partnership ("Wheatley Partners II"); o Irwin Lieber, a United States citizen; o Barry Fingerhut, a United States citizen; o Applegreen Partners, a New York general partnership ("Applegreen"); o Seth Lieber, a United States citizen; o Jonathan Lieber, a United States citizen; o Seneca Ventures, a New York limited partnership ("Seneca"); o Woodland Venture Fund, a New York limited partnership ("Woodland Venture"); o Woodland Partners, a New York general partnership ("Woodland Partners"); o Brookwood Partners, L.P., a New York limited partnership ("Brookwood"); o Barry Rubenstein, a United States citizen; and o Marilyn Rubenstein, a United States citizen. The principal business of each of Wheatley, Wheatley Foreign, Wheatley Partners II, Seneca, Woodland Venture, Woodland Partners, Brookwood and Applegreen is investing. Wheatley Partners LLC ("Wheatley LLC") is the general partner of Wheatley and a general partner of Wheatley Foreign. Messrs. Barry Rubenstein, Irwin Lieber, Seth Lieber, Jonathan Lieber and Barry Fingerhut are members and officers of Wheatley LLC and are general Page 19 of 33 partners of Wheatley Partners II. The principal place of business of Wheatley, Wheatley Foreign, Wheatley Partners II, Wheatley LLC, Messrs. Irwin Lieber, Seth Lieber, Jonathan Lieber and Barry Fingerhut is 80 Cuttermill Road, Suite 311, Great Neck, New York 11021. Barry Rubenstein is a general partner of each of Seneca, Woodland Venture, Woodland Partners and Brookwood. Woodland Services Corp., a New York corporation ("Woodland Services"), is a general partner of Seneca and Woodland Venture. Marilyn Rubenstein is a general partner of Woodland Partners and Brookwood, an officer of Woodland Services Corp. and the spouse of Mr. Rubenstein. The principal place of business of each of Seneca, Woodland Venture, Woodland Partners, Brookwood, Mr. Rubenstein, Mrs. Rubenstein and Woodland Services is 68 Wheatley Road, Brookville, New York 11545. Jonathan Lieber is the managing general partner and Seth Lieber is a general partner of Applegreen. The principal place of business of Applegreen is 8 Applegreen Drive, Old Westbury, New York 11568. Effective July 1, 2001, Applewood Capital ceased to be a general partner of Wheatley Partners II. Item 2(d) During the last five years, none of the Reporting Persons nor Wheatley LLC, nor Woodland Services has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). Item 2(e) During the last five years, none of the Reporting Persons nor Wheatley LLC, nor Woodland Services has been party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. ITEM 3. Source and Amount of Funds or Other Consideration. Item 3 is hereby amended by adding the following paragraphs: On October 2, 2001, Wheatley Partners II, Wheatley Partners, Wheatley Foreign, Woodland Venture, Seneca, Woodland Partners, Brookwood, Applegreen, Barry Rubenstein, Irwin Lieber, Barry Fingerhut, Seth Lieber and Jonathan Lieber each acquired in a private placement transaction (the "Series E Offering") 94,339 shares, 86,792 shares, 7,547 shares, 212,264 shares, 165,094 shares, 94,339 shares, 117,924 shares, 35,377 shares, 47,169 shares, 165,094 shares, 165,094 shares, 11,792 shares and 11,792 shares of Series E Convertible Preferred Stock, $0.01 par value per share (the "Series E Preferred Stock"), respectively, of the Issuer, that are immediately convertible into 188,678 shares, 173,584 shares, 15,094 shares, 424,528 shares, 330,188 shares, 188,678 shares, 235,848 shares, 70,754 shares, 94,338 shares, 330,188 shares, 330,188 shares, 23,584 shares and 23,584 shares of Common Stock, Page 20 of 33 respectively, and warrants to purchase shares of Common Stock at an exercise price of $1.27 per share, that are immediately exercisable for 188,678 shares, 173,584 shares, 15,094 shares, 424,528 shares, 330,188 shares, 188,678 shares, 235,848 shares, 70,754 shares, 94,338 shares, 330,188 shares, 330,188 shares, 23,584 shares and 23,584 shares of Common Stock, respectively. The purchase price of these securities was $199,998, $183,999, $16,000, $500,000, $349,999, $199,998, $249,998, $74,999, $99,998, $349,999, $349,999, $24,999 and $24,999, respectively. Wheatley Partners II, Wheatley, Wheatley Foreign, Woodland Venture, Seneca, Woodland Partners, Brookwood and Applegreen acquired these securities with their respective working capital and other funds. Barry Rubenstein, Irwin Lieber, Barry Fingerhut, Seth Lieber and Jonathan Lieber acquired these securities with their respective personal funds and other funds. ITEM 4. Purpose of Transaction. Item 4 is hereby amended and restated as follows: Other than the reporting persons purchase or sale of additional securities of the Issuer, no reporting person has any present plan or proposal which would relate to or result in any of the matters set forth in subparagraphs (a) - (j) of Item 4 of Schedule 13D except as set forth herein. 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 6,467,547 shares of Common Stock outstanding as reported in the Issuer's Form 10-QSB for the quarter ended June 30, 2001) of outstanding shares of Common Stock owned beneficially by each reporting person named in Item 2, as of October 2, 2001: