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                                                                   Exhibit 10.1

                       AMENDMENT TO TRANSACTION DOCUMENTS

     THIS AMENDMENT (referred to herein as this "Amendment"), dated as of March
28, 2000, by and among PRIMARK CORPORATION, a Michigan corporation (the
"Borrower"), the Lenders party to the Revolving Credit Agreement referred to
below, the Lenders party to the Note Backup Agreement referred to below (such
agreements being referred to collectively as the "Credit Facilities"), and
MELLON BANK, N.A., a national banking association, as Agent under each such
Credit Facility.

                                  RECITALS:

     A.  The Borrower has entered into (a) a Revolving Credit Agreement (as
amended, the "Revolving Credit Agreement") dated as of February 7, 1997 among
Primark Corporation (the "Borrower"), the Lenders parties thereto from time to
time, the Issuing Banks referred to therein, and Mellon Bank, N.A., as Agent,
and (b) a Note Backup Agreement (as amended, the "Note Backup Agreement") dated
as of February 7, 1997 among the Borrower, the Lenders parties thereto from time
to time, the Issuing Bank referred to therein, and Mellon Bank, N.A., as Agent
(collectively, the "Credit Facilities"). The Credit Facilities have been amended
by a letter agreement dated February 21, 1997, an Amendment to Transactions
Documents dated as of May 1, 1997, an Amendment to Transaction Documents dated
as of June 30, 1997, an Amendment to Transaction Documents dated as of December
1, 1997, an Agreement dated as of March 6, 1998 (which restated and superseded
all such prior amendments), an Amendment to Transaction Documents dated as of
May 8, 1998, an Amendment to Transaction Documents dated as of June 15, 1998, an
Amendment to Transaction Documents dated as of September 10, 1998, a Consent and
Amendment to Transaction Documents dated as of December 10, 1998, an Amendment
to Transaction Documents dated as of November 16, 1999, and an Amendment to
Transaction Documents and Waiver dated as of December 31, 1999.

     B.  The parties hereto desire to amend further the Credit Facilities as set
forth herein. Capitalized terms used herein and not otherwise defined shall
have the meanings given them in, or by reference in, the Collateral Agency
Agreement.

     NOW THEREFORE, the parties hereto, intending to be legally bound, hereby
agree as follows:

SECTION 1. LOANS, ADVANCES AND INVESTMENTS.

Section 7.05 of each Credit Facility is amended by (i) relettering existing
clause (m) as clause (n) and (ii) by inserting the following new clause (m):

     (m) Equity investment of up to $6,000,000 in TradePortal.com, Inc. ("Trade
  Portal"), which on the date of acquisition will constitute approximately 20%
  of the equity of Trade Portal;

SECTION 2. EFFECTIVENESS AND EFFECT, ETC.

     (a) EFFECTIVENESS. This Amendment shall become effective on the date when
Mellon Bank, N.A., as Agent under each of the Revolving Credit Agreement and
the Note Backup Agreement, shall have received counterparts hereof duly
executed by the Borrower and by the "Required Lenders" and the "Agent" under
each of the Revolving Credit Agreement and the Note Backup Agreement.



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     (b) EFFECT. The Revolving Credit Agreement and the Note Backup Agreement,
in the forms initially executed and as previously amended and as amended
hereby, are and shall continue to be in full force and effect, and are hereby
in all respects ratified and confirmed. Except to the extent expressly set
forth herein, the execution, delivery and effectiveness of this Amendment shall
not operate as a waiver of any right, power or remedy under any of the foregoing
agreements and instruments or constitute a waiver of any provision of any of
the foregoing agreements and instruments.

SECTION 3. MISCELLANEOUS.

This Amendment may be executed in any number of counterparts and by the
different parties hereto in separate counterparts, each of which when so
executed and delivered shall be deemed to be an original and all of which taken
together shall constitute but one and the same document. Section and other
headings herein are for reference purposes only and shall not affect the
interpretation of this Amendment in any respect. This Amendment shall be
governed by and construed in accordance with the laws of the Commonwealth of
Pennsylvania, without regard to choice of law rules. This Amendment is a
requested amendment within the meaning of Section 10.06(a) of each Credit
Facility.

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           IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be executed by their respective officers thereunto duly authorized, as of the
date first above written.

                                           PRIMARK CORPORATION

                                           By /s/ Stephen H. Curran
                                              ----------------------------------
                                           Name:  Stephen H. Curran
                                           Title: Executive Vice President & CFO


                                           MELLON BANK, N.A.,
                                           individually and as Agent under each
                                           Credit Facility

                                           By /s/ R. Jane Westrich
                                              ----------------------------------
                                                  R. Jane Westrich
                                                  Vice President


CONSENTED AND AGREED:

BANKBOSTON, N.A.
Fleet National Bank N.A. as successor/assign

By /s/ J.G. O'Donnell
   --------------------------------------
Title: Managing Director


NATIONSBANK, N.A.

By /s/ Michael R. Heredia
   --------------------------------------
Title: Managing Director


THE CHASE MANHATTAN BANK

By /s/ Neil Sweeny
   --------------------------------------
Title: Vice President



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AMSOUTH BANK,
successor in interest by merger to,
FIRST AMERICAN NATIONAL BANK

By /s/ Seth Butler
   --------------------------------------
Title: Corporate Bank Officer


WACHOVIA BANK, N.A.

By /s/ John P. Rafferty
   --------------------------------------
Title: Sr. Vice President


FLEET NATIONAL BANK

By /s/ Deanne M. Horn
   --------------------------------------
Title: Vice President


THE HUNTINGTON NATIONAL BANK

By
   --------------------------------------
Title:



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