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                                                                  EXHIBIT 10.12
                       FOURTH LOAN MODIFICATION AGREEMENT
                                   (EXIM LINE)

         This Fourth Loan Modification Agreement (Exim Line) is entered into as
of February 28, 2001, by and between OPEN MARKET, INC., a Delaware corporation
("Open Market"), with its chief executive offices located at 1 Wayside Road,
Burlington, Massachusetts 01803 and FUTURETENSE, INC., a Delaware corporation
("FutureTense"), with its chief executive offices located at 1 Wayside Road,
Burlington, Massachusetts 01803 (jointly and severally, the "Borrower") and
SILICON VALLEY BANK, a California-chartered bank ("Bank"), with its principal
place of business at 3003 Tasman Drive, Santa Clara, CA 95054 and with a loan
production office located at One Newton Executive Park, Suite 200, 2221
Washington Street, Newton, MA 02462, doing business under the name "Silicon
Valley East".

1. DESCRIPTION OF EXISTING INDEBTEDNESS. Among other indebtedness which may be
owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan
arrangement dated as of September 26, 1997, evidenced by, among other documents,
(i) a certain Export-Import Bank Loan and Security Agreement between Open
Market, Folio Corporation ("Folio") and Bank dated September 26, 1997, as
amended by a First Loan Modification Agreement (Exim Line) dated December 30,
1998, a Second Loan Modification Agreement (Exim Line) dated October 22, 1999,
an Assumption Agreement by FutureTense, Inc. dated December 12, 2000, a Third
Loan Modification Agreement (Exim Line) between Borrower and Bank dated December
12, 2000, as further amended hereby (as amended, the "Loan Agreement" or the
"Exim Agreement"), (ii) a certain Revolving Promissory Note (Export-Import Line)
dated February 28, 2001 in the maximum principal amount of Six Million Dollars
($6,000,000.00) (the "Note"), and (iii) a certain Borrower Agreement dated
February 28, 2001 (the "Borrower Agreement"). Capitalized terms used but not
otherwise defined herein shall have the same meaning as in the Loan Agreement.

Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as
the "Obligations".

2. DESCRIPTION OF COLLATERAL AND GUARANTIES. Repayment of the Obligations is
secured by the Collateral as described in the Loan Agreement (together with any
other collateral security granted to Bank, the "Security Documents").

Hereinafter, the Security Documents, together with all other documents
evidencing or securing the Obligations shall be referred to as the "Existing
Loan Documents".

3. DESCRIPTION OF CHANGE IN TERMS.

   A. Modification(s) to Loan Agreement.

      1.  The Loan Agreement shall be amended by deleting the following text
          appearing as recital paragraph (A) on Page 1 thereof:

                "Borrower and Bank are parties to that certain Loan and Security
                Agreement dated September 26, 1997 originally entered into by
                and between Open Market, Folio Corporation ("Folio") and Bank,
                as amended by a certain First Loan Modification Agreement dated
                March 20, 1998, a certain Second Loan Modification Agreement
                dated December 30, 1998, a certain Third Loan Modification
                Agreement dated October 22, 1999, a certain Assumption Agreement
                by FutureTense, Inc. dated December 12, 2000, and a certain
                Fourth Loan Modification Agreement dated December 12, 2000, as
                may be further amended from time to time (as amended, the
                "Domestic Agreement"), together with related documents."

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          and inserting in lieu thereof the following:

                "Borrower and Bank are parties to that certain Loan and Security
                Agreement dated February 28, 2001, as may be amended from time
                to time (the "Domestic Agreement"), together with related
                documents."

      2.  The Loan Agreement shall be amended by incorporating into the
          definition of "Exim Eligible Foreign Accounts" in Section 1.1 the
          following text to appear immediately after paragraph (q) thereof:

                "(r) Accounts derived from foreign maintenance agreements."

      3.  The Loan Agreement shall be amended by deleting the following
          definition appearing in Section 1.1 thereof:

                ""Exim Loan Documents" means, collectively, this Exim Agreement,
                the Domestic Loan Documents, any note or notes executed by
                Borrower, and any other agreement entered into between Borrower
                and Bank in connection with this Exim Agreement, all as amended
                or extended from time to time."

          and inserting in lieu thereof the following:

                ""Exim Loan Documents" means, collectively, this Exim Agreement,
                the Domestic Loan Documents, the Factoring Agreement, any note
                or notes executed by Borrower, and any other agreement entered
                into between Borrower and Bank in connection with this Exim
                Agreement, all as amended or extended from time to time."

      4.  The Loan Agreement shall be amended by deleting the following
          definition appearing in Section 1.1 thereof:

                ""Exim Maturity Date" means the earliest of (i) the Maturity
                Date under the Domestic Loan Documents, or (ii) January 15,
                2001."

          and inserting in lieu thereof the following:

                ""Exim Maturity Date" means the earliest of (i) the Maturity
                Date under the Domestic Loan Documents, or (ii) February 28,
                2002."

      5.  The Loan Agreement shall be amended by deleting the following text
          appearing as the last sentence of the first paragraph of Section 2.1.1
          thereof:

                "For purposes of this Exim Agreement, "Borrowing Base" shall
                mean an amount equal to ninety percent (90%) of the Exim
                Eligible Foreign Accounts."

          and inserting in lieu thereof the following:

                "For purposes of this Exim Agreement, "Borrowing Base" shall
                mean an amount equal to: (i) ninety percent (90%) of Exim
                Eligible Foreign

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                Accounts generated by Open Market, PLUS (ii) ninety percent
                (90%) of Exim Eligible Foreign Accounts generated by
                FutureTense, PLUS (iii) sixty percent (60%) of Borrower's
                eligible "foreign maintenance" Accounts (as determined by Bank)
                less than sixty (60) days from due date PROVIDED, HOWEVER, the
                aggregate availability under this Exim Agreement generated by
                the Borrower's Exim Eligible Foreign Accounts (and by "foreign
                maintenance accounts") and under the Domestic Agreement
                generated by the Borrower's Eligible Receivables (and by
                "domestic maintenance accounts") which are owed by the "Dot.Com"
                entities (as determined by Bank) shall not exceed $1,000,000.00.

                IN ADDITION TO THE BORROWING LIMITATIONS CONTAINED IN THE
                DEFINITIONS OF THE BORROWING BASE AND EXIM COMMITTED LINE AND IN
                THIS EXIM AGREEMENT, THE MAXIMUM AMOUNT OF ADVANCES HEREUNDER
                SHALL BE SUBJECT TO EACH OF THE FOLLOWING:

                      (A) Prior to the earlier of: (i) the occurrence of a
                      Capital Event (as defined in the Domestic Agreement), or
                      (ii) March 15, 2001, the outstanding Obligations
                      (including, without limitation, those arising under this
                      Exim Agreement, the Domestic Agreement and the Factoring
                      Agreement) shall not exceed at any time $4,000,000.00.

                      (B) The outstanding Obligations (including, without
                      limitation, those arising under this Exim Agreement, the
                      Domestic Agreement and the Factoring Agreement) shall not
                      exceed at any time the result of the following: (i) the
                      Borrowing Base under the Domestic Agreement, PLUS (ii) the
                      lesser of: (a) the EXIM Committed Line, or (b) the
                      Borrowing Base under this Exim Agreement, MINUS (iii)
                      $6,000,000.00.

                      (C) [Intentionally Deleted]

      6.  The Loan Agreement shall be amended by deleting in its entirety the
          following text appearing as paragraph (a) of Section 2.3 thereof:

                "(a) INTEREST RATE. Except as specified to the contrary in any
                Loan Document, any Advances under this Exim Agreement shall bear
                interest, on the average daily balance thereof, at a per annum
                rate equal to the aggregate of the Prime Rate, PLUS One Percent
                (1.0%)."

          and inserting in lieu thereof the following:

                "(a) INTEREST RATE. Except as specified to the contrary in any
                Loan Document, any Advances under this Exim Agreement shall bear
                interest, on the average daily balance thereof, at a per annum
                rate equal to the aggregate of the Prime Rate, PLUS Two Percent
                (2.0%)."

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      7.  The Loan Agreement shall be amended by incorporating into Section 2.5
          entitled "Fees" the following text to appear immediately after
          paragraph (c) thereof:

                "(d) UNUSED LINE FEE. In the event, in any calendar month (or
                portion thereof at the beginning and end of the term hereof),
                the average daily principal balance of the Advances outstanding
                during the month is less than the amount of the Exim Committed
                Line, Borrower shall pay Bank an unused line fee in an amount
                equal to 0.50% per annum on the difference between the amount of
                the Exim Committed Line and the average daily principal balance
                of the Advances outstanding during the month, which unused line
                fee shall be computed and paid monthly, in arrears, on the first
                day of the following month.

                (e) PREPAYMENT FEE. If the Obligations are voluntarily or
                involuntarily prepaid or if this Exim Agreement is otherwise
                terminated prior to its maturity, the Borrower shall pay to Bank
                a termination fee in the amount equal to 1% of the Exim
                Committed Line, provided that no such termination fee shall be
                charged if the credit facility hereunder is replaced with a new
                facility from another division of the Bank. The termination fee
                shall be due and payable upon prepayment by the Borrower in the
                case of voluntary prepayments or upon demand by Bank in the
                event of involuntary prepayment, and if not paid immediately
                shall bear interest at a rate equal to the highest rate
                applicable to any of the Obligations."

      8.  The Collateral under the Exim Agreement shall been amended to include,
          without limitation, the Collateral under the Domestic Agreement, as
          amended of even date.

      9. The Bank may place a "hold" on any deposit account, operating account
         and any other account pledged as Collateral upon and during the
         continuance of an Event of Default.

      10. It is expressly acknowledged and agreed that the security interest
          created in this Exim Agreement in all of the Collateral (with the
          exception of Exim Eligible Foreign Accounts, but only to the extent
          any Advances are actually made by the Bank to the Borrower based upon
          such Exim Eligible Foreign Accounts), is subject to and subordinate to
          the security interest granted to the Bank in the Domestic Agreement
          with respect to the Collateral.

      11. The Borrower acknowledges, confirms and agrees that its
          representations, warranties and covenants with respect to the Domestic
          Loan Documents under Sections 5.1, 6.1, 7.1 of this Exim Agreement
          (including, without limitation, the financial covenants and reporting
          requirements appearing in the Schedule to the Domestic Agreement), and
          all such other representations, warranties and covenants with respect
          to the Domestic Loan Documents appearing in the Exim Agreement, remain
          in full force and effect. The Borrower acknowledges, confirms and
          agrees that it shall continue to comply with all such representations,
          warranties and covenants described in the foregoing sentence
          notwithstanding

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          any termination of the Domestic Loan Documents or the repayment of all
          obligations under the Domestic Loan Documents.

      12. The Loan Agreement shall be amended by deleting in its entirety the
          following text appearing as Section 8.2 thereof:

                "8.2 COVENANT DEFAULT; CROSS DEFAULT. If Borrower fails or
                neglects to perform, keep, or observe any material term,
                provision, condition, covenant, or agreement contained in this
                Exim Agreement, in any of the Domestic Loan Documents, the
                Borrower Agreement or the Exim Loan Documents, or an Event of
                Default occurs under any of the Domestic Loan Documents or the
                Borrower Agreement; or"

          and inserting in lieu thereof the following:

                "8.2 COVENANT DEFAULT; CROSS DEFAULT. If Borrower fails or
                neglects to perform, keep, or observe any material term,
                provision, condition, covenant, or agreement contained in this
                Exim Agreement, in any of the Domestic Loan Documents, the
                Borrower Agreement or the Exim Loan Documents, or an Event of
                Default occurs under any of the Domestic Loan Documents or the
                Borrower Agreement, or any default under a certain Accounts
                Receivable Purchase Agreement between Bank, Open Market, Inc.
                and Folio Corporation dated December 27, 2000 (the "Factoring
                Agreement"); or"

      13. Any Event of Default under the Domestic Agreement, including, without
          limitation, those described in Section 7 thereof, shall be an Event of
          Default under the Exim Agreement, notwithstanding any termination of
          the Domestic Loan Documents and the repayment of all obligations under
          the Domestic Loan Documents.

      14. In addition to the rights and remedies of Bank described in the Exim
          Agreement, the rights and remedies of Bank under the Exim Agreement
          shall include all rights and remedies under the Domestic Agreement,
          including, without limitation, those described in Section 7 thereof,
          notwithstanding any termination of the Domestic Loan Documents and the
          repayment of all obligations under the Domestic Loan Documents.

      15. The Exim Agreement, as amended hereby, and all acts and transactions
          thereunder and all rights and obligations of Bank and Borrower shall
          be governed by the laws of the Commonwealth of Massachusetts, except
          that, with respect to Borrower's general, special, operating or other
          deposit accounts with the Bank, the Exim Agreement and all rights and
          remedies of Bank relating to such accounts shall be governed by the
          laws of the State of California.

      16. FutureTense hereby acknowledges and confirms its grant of a security
          interest to Bank in all of its right, title and interest in the
          "Collateral" defined in the Loan Agreement, as amended, and hereby
          affirmatively grants a security interest in such Collateral to the
          Bank to secure all Obligations under the Loan Agreement, as amended
          hereby.

      17. On or before the date of this Amendment, the Borrower shall: (i)
          transfer all primary operating accounts and cash management services
          to the Bank, and (ii) terminate any lock box arrangement with any
          other institution and enter into a

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          lock box arrangement with the Bank on terms satisfactory to the Bank
          pursuant to which all amounts payable to the Borrower shall be
          directed to the Bank. Any failure by Borrower to perform any
          requirement of this paragraph shall be an Event of Default under the
          Loan Agreement, as amended hereby.

      18. On or before the date of this Amendment, all bank and investment
          accounts, cash, investment property and securities of Open Market
          Securities, Inc., a Massachusetts subsidiary of Open Market, Inc.,
          shall be maintained and deposited with the Bank on terms acceptable to
          Bank as collateral under a certain Security Agreement granted by Open
          Market Securities, Inc. to Bank. Any failure by Borrower to perform
          any requirement of this paragraph shall be an Event of Default under
          the Loan Agreement, as amended hereby.

4. FEE. Borrower shall pay to Bank a fee for the modification of the
export-import line equal to Ninety Thousand Dollars ($90,000.00), which fee
shall be due on the date hereof and shall be deemed fully earned as of the date
hereof. The Borrower shall also reimburse Bank for all legal fees and expenses
incurred in connection with this amendment to the Existing Loan Documents.

5. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever
necessary to reflect the changes described above.

6. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and
reaffirms all terms and conditions of all security or other collateral granted
to the Bank, and confirms that the indebtedness secured thereby includes,
without limitation, the Obligations.

7. NO DEFENSES OF BORROWER. Borrower agrees that, as of this date, it has no
defenses against the obligations to pay any amounts under the Obligations.

8. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the
existing Obligations, Bank is relying upon Borrower's representations,
warranties, and agreements, as set forth in the Existing Loan Documents. Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect.
Bank's agreement to modifications to the existing Obligations pursuant to this
Loan Modification Agreement in no way shall obligate Bank to make any future
modifications to the Obligations. Nothing in this Loan Modification Agreement
shall constitute a satisfaction of the Obligations. It is the intention of Bank
and Borrower to retain as liable parties all makers and endorsers of Existing
Loan Documents, unless the party is expressly released by Bank in writing. No
maker, endorser, or guarantor will be released by virtue of this Loan
Modification Agreement.

9. JURISDICTION/VENUE. Borrower accepts for itself and in connection with its
properties, unconditionally, the non-exclusive jurisdiction of any state or
federal court of competent jurisdiction in the Commonwealth of Massachusetts in
any action, suit, or proceeding of any kind against it which arises out of or by
reason of this Loan Modification Agreement; provided, however, that if for any
reason Bank cannot avail itself of the courts of the Commonwealth of
Massachusetts, then venue shall lie in Santa Clara County, California.

10. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective
only when it shall have been executed by Borrower and Bank (provided, however,
in no event shall this Loan Modification Agreement become effective until signed
by an officer of Bank in California).

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         This Loan Modification Agreement is executed as of the date first
written above.

                                        ("BORROWER")

                                        OPEN MARKET, INC.

                                        By: /s/ Edward Durkin
                                            -----------------------------------
                                        Name: Edward Durkin
                                             ----------------------------------
                                        Title: Chief Financial Officer
                                              ---------------------------------

                                        FUTURETENSE, INC.

                                        By: /s/ Edward Durkin
                                            -----------------------------------
                                        Name: Edward Durkin
                                             ----------------------------------
                                        Title: Vice President
                                              ---------------------------------

                                        ("BANK")

                                        SILICON VALLEY BANK, doing business as
                                        SILICON VALLEY EAST

                                        By: /s/ John Atanasoff
                                            -----------------------------------
                                        Name: John Atanasoff
                                             ----------------------------------
                                        Title:
                                              ---------------------------------

                                        SILICON VALLEY BANK

                                        By: /s/ John Atanasoff
                                            -----------------------------------
                                        Name: John Atanasoff
                                             ----------------------------------
                                        Title:
                                              ---------------------------------
                                              (signed in Santa Clara County,
                                               California)

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