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                                                                    EXHIBIT 10.6


                          DATA BROADCASTING CORPORATION
                              3490 Clubhouse Drive
                             Jackson, Wyoming 83014


November 14, 1999

Mr. Mark F. Imperiale
12 West Road
West Orange, New Jersey 07052

Dear Mr. Imperiale:

This agreement and release (this "Letter Agreement") confirms the termination of
your status as an officer and employee of and with Data Broadcasting Corporation
(the "Company"), and each of the Company's direct and indirect subsidiaries,
such termination to be effective upon the effective time of the merger (the
"Merger") contemplated by the Agreement and Plan of Merger, dated as of the date
hereof, among the Company, Detective Merger-Sub, Inc., Interactive Data
Corporation and Pearson Longman, Inc. (the "Termination Date"). In addition, for
good and valuable consideration, the receipt of which is hereby acknowledged,
you and the Company mutually agree as follows:

1.   Termination of Employment Agreement; Resignation as Employee and Officer.
     Your execution of this Letter Agreement hereby confirms in writing your
     desire to terminate your status as an employee and officer of the Company
     and any and all of its subsidiaries, effective as of the Termination Date.
     Such execution further confirms that, except as otherwise provided herein,
     the employment agreement dated as of October 7, 1999 between you and the
     Company (the "Employment Agreement") is terminated effective as of the
     Termination Date, and all provisions thereof shall be null and void as of
     such date.

2.   Consulting Services. From the Termination Date until the earlier of the six
     month anniversary thereof or November 30, 2000 (the "Consulting Period"),
     you agree to make yourself available for consultation with the Company and
     its subsidiaries to provide, as requested, advice and information with
     respect to the business of the Company and its subsidiaries, especially
     with respect to transitional and integration issues arising by reason of
     the Merger.

3.   Payments and Benefits. You shall be entitled to the following payments and
     benefits, subject, in each case, to applicable statutory deductions and
     withholdings. Your right to receive and retain these payments and benefits
     shall be subject to your material compliance with the terms of this Letter
     Agreement (including, but not limited to, Section 6 hereof).

     (a)  In respect of your services performed for the portion of the Company's
          1999 fiscal year that you were actually employed prior to the
          Termination Date, you shall be entitled to a bonus equal to 50% of
          your base salary paid during such period, such bonus to be paid as
          soon as practicable after the Termination Date.
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     (b)  You shall be entitled to a cash payment in the amount of $75,000 per
          month, payable monthly during the Consulting Period. This payment is
          consideration for your agreement to render consulting services, and
          therefore if, after requested by the Company, you fail to perform such
          consulting services, no portion of this amount will be paid.

     (c)  You shall be entitled to a cash payment equal to $2,700,000, also
          payable at the end of the Consulting Period, but irrespective of
          whether you actually perform the consulting services requested of you.

     (d)  You shall be entitled to full vesting of any unvested stock options
          (including the "Conditional Options", as defined in the Employment
          Agreement) at the end of the Consulting Period (irrespective of
          whether you actually perform the consulting services requested of
          you), and the ability to exercise all of your outstanding options
          until the end of the three-year period following the expiration of the
          Consulting Period (or, if earlier, until the expiration of the outside
          term of each such option). You will retain the right to have your
          "Conditional Options" converted into stock appreciation rights
          pursuant to Section 3(d) of the Employment Agreement, and if such
          conversion in fact occurs, the stock appreciation rights will be
          treated as stock options for purposes of the preceding sentence.

     (e)  You shall be entitled to continued medical coverage for you and your
          family from the Termination Date until your 65th birthday at levels
          and on a basis (including cost-sharing) substantially comparable to
          those applicable to active employees of the Company or its affiliates;
          provided, however, that the Company shall not be obligated to provide
          such coverage during periods that comparable medical coverage is
          available to you or any family member by reason of your employment or
          employment of any family member. You will cooperate with the Company
          in facilitating the most cost-effective means to secure such coverage.

4.   Cessation of all other Compensation and Benefits. From and after the
     Termination Date, and except as otherwise expressly set forth in this
     Letter Agreement, you will not receive compensation, payments or benefits
     of any kind from the Company or its subsidiaries, and you expressly
     acknowledge and agree that, except with respect to the payments and
     benefits specifically set forth in this Letter Agreement, you are not
     entitled to any compensation, payment or benefit whatsoever, including,
     without limitation, any right to payment under Section 8 or 10 of the
     Employment Agreement.

5.   Payment is in Consideration of Release and Other Continuing Obligations.
     You understand and agree that the payments provided for in Section 3 of
     this Letter Agreement are being provided to you in consideration for your
     acceptance and execution of, and in reliance upon your agreements in, this
     Letter Agreement, including but not limited to the release contained
     herein.



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6.   Certain Covenants. You acknowledge and agree that Section 6
     (non-competition) and Section 7 (confidential information) of the
     Employment Agreement shall survive the termination of your employment, and
     that for purposes of Section 6 of the Employment Agreement, the restriction
     on your ability to compete will continue during the Consulting Period and
     for the one-year period thereafter.

7.   Non-Disparagement. You agree that you will not, directly or indirectly,
     disparage (whether in writing or orally) the Company or the Releasees (as
     defined below) in any manner whatsoever at any time.

8.   Release.

               (a) You hereby agree to accept the compensation, payments and
     benefits provided for in Section 3 hereof in full resolution and
     satisfaction of, and hereby IRREVOCABLY AND UNCONDITIONALLY RELEASE, REMISE
     AND FOREVER DISCHARGE the Company, its past, present and future direct and
     indirect parents (including Pearson plc and its affiliates), subsidiaries,
     affiliates, divisions, predecessors, successors, and assigns, and their
     respective current and former officers, directors, shareholders,
     representatives, agents and employees, in their official and individual
     capacities, jointly and individually (the "Releasees") from, any and all
     agreements, promises, liabilities, claims and demands of any kind
     whatsoever, in law or equity, whether known or unknown, suspected or
     unsuspected, fixed or contingent, apparent or concealed, which you, your
     respective heirs, executors, administrators, successors or assigns ever
     had, now have or in the future may have, including, without limitation, any
     and all claims arising out of or relating to your employment, the
     Employment Agreement, your compensation and benefits with the Company
     and/or the termination thereof, and any and all contract, tort or fraud
     claims, claims for defamation or other personal injury, claims under any
     federal, state or municipal wage payment, discrimination or fair employment
     practices law, statute or regulation and claims for costs, expenses and
     attorneys' fees with respect thereto, arising from the beginning of the
     world through the effective date of this Letter Agreement, in each case,
     against the Company or any of the Releasees, other than any claims with
     respect to the Company's breach of this Letter Agreement. However, it is
     agreed that you do not waive your rights for coverage or indemnification
     under any directors & officers policy, or pursuant to the certificate of
     incorporation or the by-laws of the Company for acts or omissions occurring
     during your employment. THIS RELEASE AND WAIVER INCLUDES, WITHOUT
     LIMITATION, ANY AND ALL CLAIMS UNDER THE AGE DISCRIMINATION IN EMPLOYMENT
     ACT, 29 U.S.C. "621-634 (THE "ADEA").

               (b) By signing this Letter Agreement and by acceptance of the
     compensation, payments and benefits provided for in Section 3 above, you
     hereby WAIVE, RELEASE AND COVENANT NOT TO SUE the Company or the Releasees
     with respect to any matter relating to or arising out of any claims being
     released hereunder, and you agree that you will not (i) file, charge,
     claim, sue or cause or permit to be filed any civil action, suit or legal
     proceeding for any claims which are being released hereunder against the
     Company or the Releasees, whether in the form of a federal, state or
     municipal court lawsuit or administrative agency action, an arbitration
     proceeding or otherwise, (ii) seek reinstatement or any other


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     monetary, equitable or personal relief of any kind from the Company or the
     Releasees, however that relief might be called, on the basis of any such
     claim, or (iii) accept any such relief (as described in subclause (ii)
     above) on the basis of any claims which are being released hereunder if
     sought by any person, organization or other entity other than you or acting
     for you or on your behalf. You represent and warrant as of the date hereof
     (i) that you have not filed any claim or demand for relief against the
     Company or Releasees, (ii) that there are no outstanding claims, or other
     claims or demands for relief within the meaning of this Section 8, and
     (iii) that there has been no assignment of any such claims.

9.   Future Cooperation. You agree that upon the Company's reasonable request
     (whether during or after the Consulting Period), you will use reasonable
     efforts to assist and cooperate with the Company and the Releasees in
     connection with the defense or prosecution of any claim that may be made
     against or by the Company or the Releasees, or in connection with any
     ongoing or future investigation or dispute or claim of any kind involving
     the Company or the Releasees, including any proceeding before any arbitral,
     administrative, regulatory, self-regulatory, judicial, legislative, or
     other body or agency. You will not be paid any additional amounts for any
     assistance that you provide, although you will be entitled to reimbursement
     for reasonable out-of-pocket expenses.

10.  Successors and Assigns. This Letter Agreement shall inure to the benefit of
     and shall be binding upon the parties hereto and their respective
     successors and assigns, including but not limited to (i) with respect to
     the Company, any entity with which the Company may merge or consolidate or
     to which the Company may sell substantially all of its assets, and (ii)
     with respect to you, your executors, administrators, heirs and legal
     representatives. In the event of your death, all amounts due hereunder
     shall be accelerated and immediately payable to your estate.

11.  Severability; Headings. In the event that any provision of this Letter
     Agreement shall be held by a court of proper jurisdiction to be invalid,
     void or voidable or otherwise unenforceable, the balance of this Letter
     Agreement shall continue in full force and effect unless such construction
     would clearly be contrary to the intentions of the parties or would result
     in an unconscionable injustice. The headings of the sections and paragraphs
     of this Letter Agreement are for convenience of reference only and shall
     not constitute a part hereof.

12.  Miscellaneous: Choice of Law. This Letter Agreement may be executed in
     several counterparts, each or which shall be deemed to be an original but
     all of which together will constitute one and the same instrument. This
     Letter Agreement constitutes the entire agreement, and supersedes all prior
     agreements, of the parties hereto relating to the subject matter hereof,
     and there are no written or oral terms or representations made by either
     party other than those contained herein and therein. This Letter Agreement
     cannot be modified, altered or amended except by a writing signed by all
     the parties. No waiver by either party of any provision or condition of
     this Letter Agreement at any time shall be deemed a waiver of such
     provision or condition at any prior or subsequent time or of any provision
     or condition at the same or any prior or subsequent time. This Letter
     Agreement shall be governed by and construed in accordance with the
     domestic laws of the State of Delaware, without giving effect to any choice
     of law or conflict of law provision or rule (whether of the State of


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     Delaware or any other jurisdiction) that would cause the application of the
     laws of any jurisdiction other than the State of Delaware.

13.  Facsimile Signatures Valid. Execution of this Letter Agreement with
     signatures transmitted via facsimile shall be considered valid.

                                     * * * *

If this Letter Agreement conforms to your understanding and is acceptable to
you, please indicate your agreement by signing and dating the enclosed copy of
this Letter Agreement where indicated and returning it to the Company. YOU
ACKNOWLEDGE AND AGREE THAT YOU HAVE BEEN PROVIDED WITH THE OPPORTUNITY TO HAVE A
PERIOD OF AT LEAST 21 DAYS IN WHICH TO REVIEW AND CONSIDER THIS LETTER
AGREEMENT, AND YOU HAVE USED SUCH REVIEW PERIOD TO THE EXTENT DESIRED BY YOU.
AFTER YOUR EXECUTION OF THIS LETTER AGREEMENT, YOU WILL THEN BE PERMITTED TO
REVOKE THIS LETTER AGREEMENT IN WRITING AT ANY TIME DURING THE PERIOD OF SEVEN
DAYS FOLLOWING THE EXECUTION THEREOF. IN THE EVENT THAT YOU EXECUTE THIS LETTER
AGREEMENT, THIS LETTER AGREEMENT WILL NOT BE EFFECTIVE OR ENFORCEABLE, AND NO
PAYMENTS WILL BE MADE HEREUNDER, UNTIL THE SEVEN-DAY REVOCATION PERIOD HAS
EXPIRED; UPON THE EXPIRATION OF SUCH SEVEN DAY PERIOD AFTER YOUR EXECUTION (AND
ASSUMING NO REVOCATION), THIS LETTER AGREEMENT SHALL BECOME EFFECTIVE. IN THE
EVENT THAT YOU FAIL TO EXECUTE THIS LETTER BY THE DATE SPECIFIED IN THE FIRST
SENTENCE ABOVE, OR IF YOU EXECUTE THIS LETTER AGREEMENT AND SUBSEQUENTLY ELECT
TO REVOKE THIS LETTER AGREEMENT IN WRITING PURSUANT TO THE TERMS HEREOF WITHIN
SUCH SEVEN DAY REVOCATION PERIOD, THIS LETTER AGREEMENT WILL BE OF NO FORCE OR
EFFECT, AND NO PARTY TO THIS LETTER AGREEMENT WILL HAVE ANY RIGHTS OR
OBLIGATIONS HEREUNDER.


Sincerely,

Data Broadcasting Corporation


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

THIS LETTER AGREEMENT IS A LEGAL DOCUMENT. YOU SHOULD CONSULT WITH AN ATTORNEY
PRIOR TO SIGNING THIS LETTER AGREEMENT.

BY SIGNING THIS LETTER AGREEMENT YOU ACKNOWLEDGE THAT YOU ARE COMPETENT, THAT
YOU HAVE BEEN PROVIDED WITH THE OPPORTUNITY TO HAVE A PERIOD OF AT LEAST 21 DAYS
IN WHICH TO REVIEW AND CONSIDER THIS LETTER AGREEMENT WITH AN ATTORNEY OF YOUR
CHOICE AND YOU HAVE USED SUCH REVIEW PERIOD TO THE EXTENT YOU DESIRED, THAT YOU
HAVE READ AND UNDERSTAND AND VOLUNTARILY ACCEPT THIS LETTER AGREEMENT AS FULLY
AND FINALLY RESOLVING, WAIVING AND RELEASING ANY AND ALL CLAIMS WHICH YOU MAY
HAVE AGAINST THE COMPANY AND


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RELEASEES (AS DEFINED HEREIN), INCLUDING ANY AND ALL CLAIMS UNDER THE AGE
DISCRIMINATION IN EMPLOYMENT ACT, THAT NO PROMISES OR INDUCEMENTS HAVE BEEN MADE
TO YOU EXCEPT AS SET FORTH IN THIS LETTER AGREEMENT, AND THAT YOU HAVE SIGNED
THIS LETTER AGREEMENT FREELY AND VOLUNTARILY, INTENDING TO BE LEGALLY BOUND BY
ITS TERMS. THE FOREGOING IS A SUMMARY DESCRIPTION OF THE GENERAL IMPORT OF THIS
INSTRUMENT AND DOES NOT ALTER OR AMEND THE DETAILED PROVISIONS CONTAINED IN THE
BODY HEREOF.

ACCEPTED AND AGREED:


/s/ Mark F. Imperiale                         Date:
-------------------------                          ------------------
Mark F. Imperiale






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