MODIFICATION AGREEMENT No. 3 TO
                                PROMISSORY NOTES

This MODIFICATION AGREEMENT No. 3 is made as of October 1, 2005 between Infinite
Group, Inc., a Delaware corporation with offices at 595 Blossom Road, Suite 309,
Rochester,  NY 14610 ("Borrower") and Allan Robbins,  an individual  residing at
1575 Bayshore Boulevard, Rochester, NY 14622 (the "Lender").

WHEREAS,  the Lender is the  holder of eight (8)  Convertible  Promissory  Notes
issued  by the  Borrower  to the  Lender,  as  described  in more  detail in the
attached Schedule A (collectively, the Notes); and

WHEREAS, the Lender and the Borrower are parties to a Modification Agreement No.
2 to Promissory Notes dated June 1, 2005 pursuant to which,  among other things,
the parties  agreed that the holder shall have the right in its sole  discretion
upon  written  notice to the  Borrower  at any time after  November  30, 2005 to
convert all or part of the principal amount of the Notes,  together with accrued
and unpaid interest,  for common stock of the Borrower at the conversion rate of
$.05  per  share,   as  adjusted  to  reflect   stock   splits,   distributions,
recapitalizations, etc.; and

WHEREAS, the parties desire to modify the terms and conditions of the Promissory
Notes as follows:

NOW, THEREFORE, the parties agree as follows:

      1)    The Notes and each of them are  modified to provide  that the holder
            shall have the right in its sole  discretion  upon written notice to
            the  Borrower at any time after that date which is 60 days after the
            Borrower,  following  the approval of the  Borrower's  shareholders,
            authorizes a  sufficient  number of shares of common stock to permit
            such  conversion,  to convert all or part of the principal amount of
            the Notes,  together  with accrued and unpaid  interest,  for common
            stock of the Borrower at the conversion  rate of $.05 per share,  as
            adjusted to reflect stock splits, distributions,  recapitalizations,
            etc.

      2)    The conversion of the Notes and accrued  interest  thereon to common
            stock shall be limited such that the Borrower  incurs no  limitation
            of the use of its net  operating  loss  carryforwards,  which may be
            triggered  by  a  change  of  control   involving  one  or  more  5%
            shareholders.  The Borrower  shall  provide  Lender with  sufficient
            information,  including  the  opinion of an  accountant  or attorney
            reasonably  acceptable to Lender, prior to completing the conversion
            to document  that a change of control  will not occur as a result of
            Lender's  request to convert all of part of the Notes and/or accrued
            interest.

            If one or more holders of  convertible  promissory  notes exist with
            conversion  rights that may result in ownership of 5% or more of the
            common  stock  of  Borrower,  then  Borrower  shall  provide  timely
            notification  to all other such  promissory note holders of Lender's
            request for conversion of promissory  notes and/or accrued  interest
            to common  stock.  Such  notice  shall  provide  the other such note
            holders an opportunity  to request a conversion  within ten business
            days of notification. The Borrower shall include all such conversion
            requests in aggregate  and document that a change of control has not
            occurred prior to completing each note holder's  conversion.  Lender
            agrees to adjust its  request for  conversion  on a pari passu basis
            with each  other note  holder's  request so that a change of control
            does not  occur  when all notes  holder's  conversion  requests  are
            considered in aggregate.


<PAGE>

            If the Borrower  closes a  transaction  with another  third party or
            parties  that   results  in  a  change  of  control  that   triggers
            limitations  of its  net  operating  loss  carryforwards,  then  the
            provisions of this section 2) shall no longer be in effect.

      3)    The interest  rate on the Notes shall be increased to eight  percent
            (8%) per annum effective January 1, 2006.

      4)    Except as modified by this  Agreement,  all of the terms,  covenants
            and conditions of the Notes shall remain the same.

In witness  whereof,  Borrower and the Lender have executed this Agreement under
the day and year first written above.

INFINITE GROUP, INC.


/s/ Michael S. Smith
--------------------
By: Michael S. Smith, President


/s/ Allan Robbins
-----------------
Allan Robbins


<PAGE>

              CONVERTIBLE PROMISSORY NOTES OF INFINITE GROUP, INC.
                            IN FAVOR OF ALLAN ROBBINS


Holder                           Principal Amt                          Date

Allan Robbins                      $  25,000                            2/25/03
Allan Robbins                      $  15,000                            4/15/03
Allan Robbins                      $  60,000                            4/25/03
Allan Robbins                      $  40,000                            5/22/03
Allan Robbins                      $  60,000                             7/2/03
Allan Robbins                      $  40,000                            12/4/03
Allan Robbins                      $   4,000                             1/2/04
Allan Robbins                      $  70,000                            2/26/04