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                                                                    Exhibit 10.9


                        EXECUTIVE STOCK PLEDGE AGREEMENT


                  THIS EXECUTIVE STOCK PLEDGE AGREEMENT (this "PLEDGE
AGREEMENT") is made as of September 7, 2001 between Jack Pearlstein
("PLEDGOR") and DigitalNet Holdings, Inc. (the "COMPANY").

                  The Company and Pledgor are parties to a Senior Management
Agreement, dated as of September 7, 2001 (the "SENIOR MANAGEMENT AGREEMENT"),
pursuant to which Pledgor will purchase up to 1,577,784 shares of the Company's
Common Stock, $0.001par value per share (the "RESERVED SHARES"), for an
aggregate purchase price of up to $155,778. The aggregate number of Reserved
Shares will be purchased over time by Pledgor in accordance with Sections
1(a)(i) and 1(b)(ii) of the Senior Management Agreement (a "RESERVED SHARE
PURCHASE"). The Company has allowed Pledgor to purchase a portion of the
Reserved Shares by delivery to the Company of a revolving promissory note (the
"NOTE"). As set forth in Section 2 of the Senior Management Agreement, from time
to time the Company may repurchase all or a portion of the Reserved Shares ( a
"RESERVED SHARE REPURCHASE"), which shall reduce the number of Reserved Shares
held by the Pledgor. The number of Reserved Shares held at any time by the
Pledgor (as adjusted for Reserved Share Purchases and Reserved Share
Repurchases) shall be defined as the "PLEDGED SHARES." This Pledge Agreement
provides the terms and conditions upon which the Note is secured by a pledge to
the Company of the Pledged Shares.

                  NOW, THEREFORE, in consideration of the premises contained
herein and other good and valuable consideration the receipt and sufficiency of
which are hereby acknowledged, and in order to induce the Company to accept the
Note as partial payment for the Pledged Shares, Pledgor and the Company hereby
agree as follows:

                  1. PLEDGE. Pledgor hereby pledges to the Company, and grants
to the Company a security interest in, the Pledged Shares as security for the
prompt and complete payment when due of the unpaid principal of and interest on
the Note and full payment and performance of the obligations and liabilities of
Pledgor hereunder.

                  2. DELIVERY OF PLEDGED SHARES. Upon the execution of this
Pledge Agreement and upon any Reserved Share Purchase, Pledgor shall deliver to
the Company the certificate(s) representing the Pledged Shares, together with
duly executed forms of assignment sufficient to transfer title thereto to the
Company.

                  3. VOTING RIGHTS; CASH DIVIDENDS. Notwithstanding anything to
the contrary contained herein, during the term of this Pledge Agreement until
such time as there exists a default in the payment of principal or interest on
the Note or any other default under the Note or hereunder, Pledgor shall be
entitled to all voting rights with respect to the Pledged Shares and shall be
entitled to receive all cash dividends paid in respect of the Pledged Shares.
Upon the occurrence of and during the continuance of any such default, Pledgor
shall no longer be able to

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vote the Pledged Shares and the Company shall apply all such cash dividends
payable on the Pledged Shares against any unpaid portion of the Note.

                  4. STOCK DIVIDENDS; DISTRIBUTIONS, ETC. If, while this Pledge
Agreement is in effect, Pledgor becomes entitled to receive or receives any
securities or other property in addition to, in substitution of, or in exchange
for any of the Pledged Shares (whether as a distribution in connection with any
recapitalization, reorganization or reclassification, a stock dividend or
otherwise), Pledgor shall accept such securities or other property on behalf of
and for the benefit of the Company as additional security for Pledgor's
obligations under the Note and shall promptly deliver such additional security
to the Company together with duly executed forms of assignment, and such
additional security shall be deemed to be part of the Pledged Shares hereunder.

                  5. DEFAULT. If Pledgor defaults in the payment of the
principal or interest under the Note when it becomes due (whether upon demand,
acceleration or otherwise) or any other event of default under the Note or this
Pledge Agreement occurs (including, without limitation, the bankruptcy or
insolvency of Pledgor), the Company may exercise any and all the rights, powers
and remedies of any owner of the Pledged Shares (including, without limitation,
the right to vote the shares and receive dividends and distributions with
respect to such shares) and shall have and may exercise without demand any and
all the rights and remedies granted to a secured party upon default under the
Uniform Commercial Code of Delaware or otherwise available to the Company under
applicable law. Without limiting the foregoing, the Company is authorized to
sell, assign and deliver at its discretion, from time to time, all or any part
of the Pledged Shares at any private sale or public auction, on not less than
ten days written notice to Pledgor, at such price or prices and upon such terms
as the Company may deem advisable. Pledgor shall have no right to redeem the
Pledged Shares after any such sale or assignment. At any such sale or auction,
the Company may bid for, and become the purchaser of, the whole or any part of
the Pledged Shares offered for sale. In case of any such sale, after deducting
the costs, attorneys' fees and other expenses of sale and delivery, the
remaining proceeds of such sale shall be applied to the principal of and accrued
interest on the Note; provided that after payment in full of the indebtedness
evidenced by the Note, the balance of the proceeds of sale then remaining shall
be paid to Pledgor and Pledgor shall be entitled to the return of any of the
Pledged Shares remaining in the hands of the Company. Pledgor shall be liable
for any deficiency if the remaining proceeds are insufficient to pay the
indebtedness under the Note in full, including, without limitation, the fees of
any attorneys employed by the Company to collect such deficiency.

                  6. COSTS AND ATTORNEYS' FEES. All reasonable costs and
expenses (including, without limitation, attorneys' fees) incurred in exercising
any right, power or remedy conferred by this Pledge Agreement or in the
enforcement thereof, shall become part of the indebtedness secured hereunder and
shall be paid by Pledgor or repaid from the proceeds of the sale of the Pledged
Shares hereunder.

                  7. PAYMENT OF INDEBTEDNESS AND RELEASE OF PLEDGED SHARES. Upon
payment in full of the indebtedness evidenced by the Note, the Company shall
surrender all of the Pledged Shares (and any dividends held as security) to
Pledgor together with all forms of assignment.

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Upon a Reserved Share Repurchase, the Company shall surrender to the purchaser
of the Reserved Shares (upon receipt of payment therefor) the number of Reserved
Shares being repurchased together with all forms of assignment.

                  8. NO OTHER LIENS; NO SALES OR TRANSFERS. Pledgor hereby
represents and warrants that he has good and valid title to all of the Pledged
Shares, free and clear of all liens, security interests and other encumbrances,
other than pursuant to the Senior Management Agreement and a Stockholders
Agreement dated as of September 7, 2001 among the Company and certain of its
stockholders (including, without limitation, Pledgor), and Pledgor hereby
covenants that, until such time as all of the outstanding principal of and
interest on the Note has been repaid, Pledgor shall not (i) create, incur,
assume or suffer to exist any pledge, security interest, encumbrance, lien or
charge of any kind against the Pledged Shares or Pledgor's rights or a holder
thereof, other than pursuant to this Agreement, or (ii) sell or otherwise
transfer any Pledged Shares or any interest therein.

                  9. FURTHER ASSURANCES. Pledgor agrees that at any time and
from time to time upon the written request of the Company, Pledgor shall execute
and deliver such further documents (including UCC financing statements) and do
such further acts and things as the Company may reasonably request in order to
effect the purposes of this Pledge Agreement.

                  10. SEVERABILITY. Any provision of this Pledge Agreement which
is prohibited or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof, and any
such prohibition or unenforceability in any jurisdiction shall not invalidate or
render unenforceable such provision in any other jurisdiction.

                  11. NO WAIVER; CUMULATIVE REMEDIES. The Company shall not by
any act, delay, omission or otherwise be deemed to have waived any of its rights
or remedies hereunder, and no waiver shall be valid unless in writing, signed by
the Company, and then only to the extent therein set forth. A waiver by the
Company of any right or remedy hereunder on any one occasion shall not be
construed as a bar to any right or remedy which the Company would otherwise have
on any future occasion. No failure to exercise nor any delay in exercising on
the part of the Company, any right, power or privilege hereunder shall preclude
any other or further exercise thereof or the exercise of any other right, power
or privilege. The rights and remedies herein provided are cumulative and may be
exercised singly or concurrently, and are not exclusive of any rights or
remedies provided by law.

                  12. WAIVERS, AMENDMENTS; APPLICABLE LAW. None of the terms or
provisions of this Pledge Agreement may be waived, altered, modified or amended
except by an instrument in writing, duly executed by the parties hereto. This
Agreement and all obligations of the Pledgor hereunder shall together with the
rights and remedies of the Company hereunder, inure to the benefit of the
Company and its successors and assigns. This Pledge Agreement shall be governed
by, and be construed and interpreted in accordance with, the laws of the State
of Delaware.

                                    * * * * *

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                  IN WITNESS WHEREOF, this Pledge Agreement has been executed as
of the date first above written.


                                         DIGITALNET HOLDINGS, INC.


                                         By: /s/ KEN S. BAJAJ
                                             ----------------------------------

                                         Name: KEN S. BAJAJ
                                               --------------------------------

                                         Its: CHIEF EXECUTIVE OFFICER
                                              ----------------------------------


                                         /s/ Jack Pearlstein
                                         ---------------------------------------
                                         JACK PEARLSTEIN



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