================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                   FORM 12B-25

                                                  Commission File Number 1-14896

                           NOTIFICATION OF LATE FILING

(Check One):

 [X]Form 10-KSB   [ ]Form 11-K   [ ]Form 20-F   [ ]Form 10-QSB   [ ]Form N-SAR


For Period Ended: December 31, 2000
                  -----------------

[ ]  Transition Report on Form 10-K       [ ]  Transition Report on Form 10-Q
[ ]  Transition Report on Form 20-F       [ ]  Transition Report on Form N-SAR
[ ]  Transition Report on Form 11-K

For the Transition Period Ended:_____________________

  READ ATTACHED INSTRUCTION SHEET BEFORE PREPARING FORM. PLEASE PRINT OR TYPE.

     Nothing in this form shall be construed to imply that the Commission has
verified any information contained herein.

     If the notification relates to a portion of the filing checked above,
identify the Item(s) to which the notification relates:

- --------------------------------------------------------------------------------

                         PART I. REGISTRANT INFORMATION

              Full name of registrant; Former name if applicable:

                       Network-1 Security Solutions, Inc.
                       ----------------------------------

           Address of principal executive office (Street and number):

                       1601 Trapelo Road, Reservoir Place
                       -----------------------------------

City, State and Zip Code:       Waltham, Massachusetts 02451
                          -----------------------------------

                        PART II. RULE 12B-25 (B) AND (C)

     If the subject report could not be filed without unreasonable effort or
expense and the registrant seeks relief pursuant to Rule 12b-25(b), the
following should be completed. (Check appropriate box.)

[X]  (a) The reasons described in reasonable detail in Part III of this form
     could not be eliminated without unreasonable effort or expense;

[X]  (b) The subject annual report, semi-annual report, transition report on
     Form 10-K, 20-F, 11-K or Form N-SAR, or portion thereof will be filed on or
     before the 15th calendar day following the prescribed due date; or the
     subject quarterly report or transition report on Form 10-Q, or portion
     thereof will be filed on or before the fifth calendar day following the
     prescribed due date; and

[ ]  (c) The accountant's statement or other exhibit required by Rule 12b-25(c)
     has been attached if applicable.
================================================================================


                               PART III. NARRATIVE

     State below in reasonable detail the reasons why Form 10-K, 11-K, 20-F,
10-Q, N-SAR or the transition report portion thereof could not be filed within
the prescribed time period. (Attach extra sheets if needed.)

     The Company is unable to file its Form 10-KSB for the year ended December
31, 2000 at this time because certain accounting issues remain outstanding which
cannot be resolved without unreasonable effort or expense.

                           PART IV. OTHER INFORMATION

     (1) Name and telephone number of person to contact in regard to this
notification

Murray P. Fish                     (781)                       522-3400
- --------------------------------------------------------------------------------
(Name)                          (Area Code)               (Telephone number)

     (2) Have all other periodic reports required under Section 13 or 15(d) of
the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act
of 1940 during the preceding 12 months or for such shorter period that the
registrant was required to file such report(s) been filed? If the answer is no,
identify report(s).
                                                                [X] Yes  [ ] No

     (3) Is it anticipated that any significant change in results of operations
from the corresponding period for the last fiscal year will be reflected by the
earnings statements to be included in the subject report or portion thereof?

                                                                [X] Yes  [ ] No

     If so: attach an explanation of the anticipated change, both narratively
and quantitatively, and, if appropriate, state the reasons why a reasonable
estimate of the results cannot be made. See attachment.


                       Network-1 Security Solutions, Inc.
- --------------------------------------------------------------------------------
                  (Name of registrant as specified in charter)

Has caused this notification to be signed on its behalf by the undersigned
thereunto duly authorized.

Date: April 2, 2001                     By: /s/ Murray P. Fish
    ----------------                        ------------------------------
                                            Name: Murray P. Fish
                                            Title: Chief Financial Officer

     INSTRUCTION. The form may be signed by an executive officer of the
registrant or by any other duly authorized representative. The name and title of
the person signing the form shall be typed or printed beneath the signature. If
the statement is signed on behalf of the registrant by an authorized
representative (other than an executive officer), evidence of the
representative's authority to sign on behalf of the registrant shall be filed
with the form.



                                   Attachment

                 Form 12b-25/Network-1 Security Solutions, Inc.

(3)      The Company anticipates that it will incur a net loss of approximately
         $4,800,000 for the year ended December 31, 2000 as compared to a net
         loss of $6,946,000 for the year ended December 31, 1999.