[INTERACTIVE DATA CORPORATION LETTERHEAD]

Exhibit 10.50

[INTERACTIVE DATA CORPORATION

LETTERHEAD]

PERSONAL

Mr. Mark Hepsworth

176 Riverside Avenue

Riverside, CT 06878

December 3, 2008

Dear Mark:

This contract (the “Secondment Second Extension Contract”) sets forth the revised terms of your secondment to Interactive Data Corporation (“IDCO”). This contract reflects an extension of your original secondment period as set forth in the agreement between you and Interactive Data (Europe) Limited (f/k/a FT Interactive Data (Europe) Limited) (the “IDCO-Europe”) dated September 1, 2005, as extended by the Secondment Extension Contract dated October 30, 2007 (the “Original Secondment Contract”). This Secondment Second Extension Contract amends and supersedes the Original Secondment Contract in its entirety effective as of the Extension Date set forth below. This Secondment Second Extension Contract is subject to the approval of IDCO’s Compensation Subcommittee and is considered supplementary to your basic contract of employment (“Employment Contract”) (dated 23 May 1995 and amended on 2 April 2003) with IDCO-Europe. At all times during the period of your secondment, you will remain an employee IDCO-Europe employed under and subject to your existing terms and conditions of employment, save as amended below. Your secondment and this Secondment Second Extension Contract are not intended to be, and shall not create, a contract of employment between yourself and IDCO or any of its subsidiaries in the United States.

At the end of your secondment, you will revert to the terms and conditions of your Employment Contract, save in relation to your job role, as to which please see further below.

The conditions of your secondment to IDCO in the United States are as follows:

ASSIGNMENT DETAILS

Items 1 to 21 are based upon known current tax rates, currency exchange rate, applicable employee benefits etc. and may be varied by IDCO should substantial changes occur to the same.

1

REMUNERATION

SECONDMENT ALLOWANCES

2

3

OTHER

Appendix A of your Employment Contract is amended mutatis mutandis such that the obligations and rights set forth on Appendix A in the sections entitled, “Data Protection”, “Outside Interests”, “Copyright”, and “Restrictive Covenants” apply not only to IDCO-Europe but to Interactive Data Corporation, and each of its subsidiaries.

During the Secondment Second Extension Term you agree that IDCO and IDCO-Europe are authorized to deduct from your salary any deductions that any competent taxation authority requires to be deducted and that you will indemnify and keep indemnified IDCO and its subsidiaries from and against any outstanding liability to any competent taxation authority in respect of any sums found due in respect of the payment of salary to you.

Upon the successful completion of this Secondment Second Extension Contract, you will be offered the opportunity to return to a position within IDCO-Europe. The cost of returning you and your family to your Home Unit, including the cost of direct route business class airfare and the shipment of household and personal effects will be borne by IDCO-Europe as set forth above. If a position comparable to your current position (and at a salary of no less than £185,500 but excepting those elements related to expatriate status, e.g., housing allowance, private school fees or, if greater, your then base salary at the IDCO budget exchange rate in effect at that time) is not available and your employment is terminated by reason of redundancy you will be entitled to severance in accordance with IDCO’s U.K. Severance Policy provided, however, that any severance payments made to you pursuant to the UK Severance Policy shall be made in a lump sum no later than March 15^th of the year following the year in which your employment is terminated and otherwise in a manner so as to be exempt from the requirements of Section 409A of the Code (as defined below) under the short term deferral exception.

If your employment is terminated by IDCO-Europe during the Secondment Second Extension Term for any reason other than one justifying summary dismissal without notice under your employment terms or common law, IDCO will pay the repatriation costs specified above. If you resign during the Secondment Second Extension Term to accept an offer of employment by another company, IDCO shall have no obligation to pay any repatriation any costs.

If any provision of this Secondment Second Extension Contract would, in the reasonable, good faith judgment of the IDCO General Counsel, contravene any regulations or U.S. Treasury guidance promulgated under Section 409A of the U.S. Internal Revenue Code of 1986, as amended (the “Code”) or could cause payment to be subject to the interest and penalties under Section 409A of the Code, such provision of this contract shall be modified to maintain, to the maximum extent practicable, the original intent of the applicable provision without violating the provisions of Section 409A of the Code.

4

Anything in this Secondment Second Extension Contract to the contrary notwithstanding, no reimbursement or other amount payable to you pursuant to any provisions of this Secondment Second Extension Contract or to any plan or arrangement of Pearson, IDCO or any of its subsidiaries, covered by this Secondment Second Extension Contract shall be paid later than the last day of the calendar year following the calendar year in which the related expense was incurred, except to the extent that the right to reimbursement does not provide for a “deferral of compensation” within the meaning of Section 409A of the Code. No amount reimbursed during any calendar year shall affect the amounts eligible for reimbursement in any other calendar year.

This Secondment Second Extension Contract and the relationships of the parties in connection with the subject matter of this contract shall be governed by, and construed in accordance with, the laws of England and Wales.

To indicate that you understand and accept the contents of this Secondment Second Extension Contract, please sign, date and return to me the duplicate of this contract. If you have any questions regarding the secondment policy or process, please contact me or Peter Castrichini at ###-###-####.

Signed for and on behalf of

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