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                                                                    EXHIBIT 99.4
 
                              PRIMARK CORPORATION
 
                           OFFER FOR ALL OUTSTANDING
                   9 1/4% SENIOR SUBORDINATED NOTES DUE 2008
                                IN EXCHANGE FOR
              9 1/4% SENIOR SUBORDINATED EXCHANGE NOTES DUE 2008,
                          THE SECURITIES ACT OF 1933,
                                   AS AMENDED
 
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   THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
             , 1999, UNLESS EXTENDED (THE "EXPIRATION DATE"). TENDERS MAY BE 
   WITHDRAWN PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE.
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To: Brokers, Dealers, Commercial Banks,
    Trust Companies and Other Nominees:
 
     Primark Corporation (the "Company") is offering, upon and subject to the
terms and conditions set forth in the Prospectus, dated           , 1999 (the
"Prospectus"), and the enclosed Letter of Transmittal (the "Letter of
Transmittal"), to exchange (the "Exchange Offer") its 9 1/4% Senior Subordinated
Notes due 2008, which have been registered under the Securities Act of 1933, as
amended, for its outstanding 9 1/4% Senior Exchange Subordinated Notes due 2008
(the "Old Notes"). The Exchange Offer is being made in order to satisfy certain
obligations of the Company contained in the Registration Rights Agreement dated
December 16, 1998, by and among the Company and the initial purchasers referred
to therein.
 
     We are requesting that you contact your clients for whom you hold Old Notes
regarding the Exchange Offer. For your information and for forwarding to your
clients for whom you hold Old Notes registered in your name or in the name of
your nominee, or who hold Old Notes registered in their own names, we are
enclosing the following documents:
 
          1. Prospectus dated           , 1999;
 
          2. The Letter of Transmittal for your use and for the information of
     your clients;
 
          3. A Notice of Guaranteed Delivery to be used to accept the Exchange
     Offer if certificates for Old Notes are not immediately available or time
     will not permit all required documents to reach the Exchange Agent prior to
     the Expiration Date (as defined below) or if the procedure for book-entry
     transfer cannot be completed on a timely basis;
 
          4. A form of letter which may be sent to your clients for whose
     account you hold Old Notes registered in your name or the name of your
     nominee, with space provided for obtaining such clients' instructions with
     regard to the Exchange Offer;
 
          5. Guidelines for Certification of Taxpayer Identification Number on
     Substitute Form W-9; and
 
          6. Return envelopes addressed to State Street Bank and Trust Company,
     the Exchange Agent for the Exchange Offer.
 
     YOUR PROMPT ACTION IS REQUESTED. THE EXCHANGE OFFER WILL EXPIRE AT 5:00
P.M., NEW YORK CITY TIME, ON           , 1999, UNLESS EXTENDED BY THE COMPANY
(THE "EXPIRATION DATE"). OLD NOTES TENDERED PURSUANT TO THE EXCHANGE OFFER MAY
BE WITHDRAWN AT ANY TIME BEFORE THE EXPIRATION DATE.
 
     To participate in the Exchange Offer, a duly executed and properly
completed Letter of Transmittal (or facsimile thereof), with any required
signature guarantees and any other required documents, should be sent to the
Exchange Agent and certificates representing the Old Notes should be delivered
to the Exchange Agent, all in accordance with the instructions set forth in the
Letter of Transmittal and the Prospectus.
 
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     If a registered holder of Old Notes desires to tender, but such Old Notes
are not immediately available, or time will not permit such holder's Old Notes
or other required documents to reach the Exchange Agent before the Expiration
Date, or the procedure for book-entry transfer cannot be completed on a timely
basis, a tender may be effected by following the guaranteed delivery procedures
described in the Prospectus under the caption "The Exchange Offer-Guaranteed
delivery procedures."
 
     The Company will, upon request, reimburse brokers, dealers, commercial
banks and trust companies for reasonable and necessary costs and expenses
incurred by them in forwarding the Prospectus and the related documents to the
beneficial owners of Old Notes held by them as nominee or in a fiduciary
capacity. The Company will pay or cause to be paid all stock transfer taxes
applicable to the exchange of Old Notes pursuant to the Exchange Offer, except
as set forth in Instruction 6 of the Letter of Transmittal.
 
     Any inquiries you may have with respect to the Exchange Offer, or requests
for additional copies of the enclosed materials, should be directed State Street
Bank and Trust Company, the Exchange Agent for the Exchange Offer, at its
address and telephone number set forth on the front of the Letter of
Transmittal.
 
                                         Very truly yours,
 
                                         PRIMARK CORPORATION
 
     NOTHING HEREIN OR IN THE ENCLOSED DOCUMENTS SHALL CONSTITUTE YOU OR ANY
PERSON AS AN AGENT OF THE COMPANY OR THE EXCHANGE AGENT, OR AUTHORIZE YOU OR ANY
OTHER PERSON TO USE ANY DOCUMENT OR MAKE ANY STATEMENTS ON BEHALF OF EITHER OF
THEM WITH RESPECT TO THE EXCHANGE OFFER, EXCEPT FOR STATEMENTS EXPRESSLY MADE IN
THE PROSPECTUS OR THE LETTER OF TRANSMITTAL.
 
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