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                                                                   Exhibit 10.28

                             VALIDUS HOLDINGS, LTD.
                             STOCK OPTION AGREEMENT

          AGREEMENT, made and entered into this 4th day of February, 2006 by and
between Validus Holdings, Ltd. (the "Company"), a Bermuda corporation, and
Edward Noonan (the "Option Holder").

          WHEREAS, the Option Holder has been designated to participate in the
Validus Holdings, Ltd. 2005 Long Term Incentive Plan (the "Plan");

          NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, and for other good and valuable consideration, the Company and
the Option Holder agree as follows:

          (a) Grant. Pursuant to the provisions of the Plan, the terms of which
are incorporated herein by reference, the Company hereby grants to the Option
Holder the right and option (the "Option") to purchase 1,294,721 Shares. The
Option is granted as of February 4, 2006, and such grant is subject to the terms
and conditions herein and the terms and conditions of the Plan. Such Option is
not intended to be treated as an incentive stock option under Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code"). In the event there is
any conflict between the terms of the Plan and this Agreement, the terms of the
Plan shall control. Capitalized terms used herein but not defined shall have the
meanings given to them in the Plan.

          (b) Purchase Price. The purchase price of the Shares subject to the
Option shall be equal to $10.00 per Share.

          (c) Term of Option. The Option may be exercised only during the period
commencing on the date it vests and becomes exercisable under paragraph (d)
below and continuing until the close of business on December 12, 2015 (the
"Option Period"). The Option Holder's exercise rights during the Option Period
shall be subject to limitations as hereinafter provided and shall be subject to
sooner termination as provided in paragraph (e) below. At the end of the Option
Period or, if earlier, the termination of the period of exercisability as
provided in paragraph (e), below, the Option shall terminate.

          (d) Exercisability. Except as otherwise provided in paragraphs (f) or
(h) below, the Option shall vest and become exercisable in five equal annual
installments, beginning on December 12, 2006 and continuing on each of the
following four anniversaries of December 12, 2006.

          (e) Termination. Except as otherwise set forth in paragraph (f) below,
the following provisions apply in the event of Termination of Service of the
Option Holder.

               (i) (A) Death in Service. In the event of Termination of Service
of the Option Holder by reason of the Option Holder's death, the Option Holder's
estate or other legal representative shall be entitled to exercise the portion
of the Option exercisable at the time of death,

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if any, determined in accordance with paragraph (d) above, and such portion of
the Option shall continue to be exercisable by the estate or other legal
representative of the Option Holder during the period ending one (1) year
following the date of death (but not beyond the Option Period).

                    (B) Death After Service. In the event the Option Holder dies
after his or her Termination of Service at a time when all or a portion of the
Option remains exercisable, the estate or other legal representative of the
Option Holder shall be entitled to exercise the portion of the Option that
remains exercisable during the period the Option Holder would have been eligible
to exercise the Option had the Option Holder not died.

               (ii) Termination Due to Disability. In the event of Termination
of Service of the Option Holder by reason of the Option Holder's Disability (as
defined in the Employment Agreement (as defined below)), the Option Holder shall
be entitled to exercise the portion of the Option exercisable at the time of
such Termination of Service, if any, determined in accordance with paragraph (d)
above, and such portion of the Option shall continue to be exercisable by the
Option Holder during the period ending one (1) year following the date of
Termination of Service (but not beyond the Option Period).

               (iii) Termination for Cause. In the event of Termination of
Service of the Option Holder by the Company or its Subsidiaries for Cause, all
rights of the Option Holder to exercise the Option granted to the Option Holder
shall be forfeited immediately and the Option shall terminate. For purposes of
this Agreement, "Cause" shall have the meaning set forth in the Option Holder's
employment agreement with the Company or a Subsidiary (the "Employment
Agreement").

               (iv) Termination Not For Cause or For Good Reason. If the
Employment Period (as defined in the Employment Agreement) shall be terminated
by the Option Holder for Good Reason (as defined in the Employment Agreement) or
by the Company without Cause, the Option shall continue to vest through the Date
of Termination (as defined in the Employment Agreement) and the exercisable
portion of the Option shall continue to be exercisable by the Option Holder
during the period ending ninety (90) days following the Date of Termination (but
not beyond the Option Period). For the avoidance of doubt, the Option will
continue to vest under this clause (iv) only if and to the extent a vesting
date, as set forth in (d) above, occurs on or prior to the Date of Termination.

               (v) Resignation Without Good Reason. If the Employment Period
shall be terminated as a result of the Option Holder's resignation or leaving of
his employment, other than for Good Reason, no portion of the Option shall vest
on or following the date the Option Holder provides Notice of Termination (as
defined in the Employment Agreement) without Good Reason to the Company (the
"Notice Date"), the Option Holder shall be entitled to exercise only the portion
of the Option exercisable on such Notice Date, if any, determined in accordance
with paragraph (d) above, and such portion of the Option shall continue to be
exercisable by the Option Holder for ninety (90) days following the Notice Date
(but not beyond the Option Period).

               (vi) Forfeiture. That portion of the Option which is
unexercisable immediately following the Option Holder's Termination of Service
(in the case of clauses (i), (ii) or

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(iii) above), following the Date of Termination (in the case of clause (iv)
above), or following the Notice Date (in the case of clause (v) above) shall be
immediately forfeited to the Company.

          (f) Continuation as Director. Notwithstanding any provision of this
Agreement to the contrary, if the Option Holder's employment by the Company
terminates but he continues to serve on the Board, (i) 50% of the unvested
Option, if any, shall continue to vest and become exercisable in accordance with
the schedule set forth in paragraph (d) above for so long as the Option Holder
continues to serve on the Board, (ii) the remaining 50% of the unvested Option,
if any, shall be immediately forfeited to the Company upon such termination of
employment, (iii) the Option, to the extent it is or becomes vested, will
continue to be exercisable until ninety (90) days after the Option Holder ceases
to be a member of the Board (but not beyond the Option Period), and (iv) any
portion of the Option which is unexercisable at the time of the Option Holder's
termination of service on the Board shall be immediately forfeited to the
Company; provided, however, that if, after becoming a nonemployee member of the
Board, the Employee is involuntarily removed from the Board, or after having
agreed to stand for reelection is not reelected to the Board, in either case not
due to circumstances that would constitute Cause under the Employment Agreement,
then any unvested Options that were not previously forfeited shall become vested
at the time the Employee ceases to be member of the Board.

          (g) Exercise of Option. In order to exercise the Option, the Option
Holder shall submit to the Company an instrument in writing specifying the
number of Shares in respect of which the Option is being exercised, accompanied
by payment, in a manner acceptable to the Committee, of the Option Price of the
Shares in respect of which the Option is being exercised. Shares shall then be
issued by the Company; provided, however, that the Company shall not be
obligated to issue any Shares hereunder if the issuance of such Shares would
violate the provisions of any applicable law.

          (h) Change in Control. Notwithstanding any provision of this Agreement
to the contrary, if, within two years following a Change in Control, the Option
Holder's employment is terminated by the Company not for Cause or by the Option
Holder for Good Reason, the Option shall become immediately vested and
exercisable in full upon such termination of employment. For purposes of this
Agreement, "Change in Control" shall have the meaning set forth in the Plan.

          (i) No Rights of Shareholder; No Rights of Continued Employment. The
Option Holder shall not, by virtue of the Option, be entitled to any rights of a
shareholder of the Company until Shares are issued to the Option Holder. The
grant of the Option shall not confer on the Option Holder any right with respect
to continuance of the Option Holder's service with the Company nor shall such
grant interfere in any way with the right of the Company to terminate the Option
Holder's service at any time.

          (j) Nonassignability. The Option may be assigned or otherwise
transferred only in the following circumstances: (i) by will or the laws of
descent and distribution; (ii) by valid beneficiary designation taking effect at
death made in accordance with procedures established by the Committee; or (iii)
by the Option Holder to members of the Option Holder's "immediate family," to a
trust established for the exclusive benefit of solely one or more members of the
Option Holder's "immediate family" and/or the Option Holder, or to a
partnership, limited liability company or other entity under which the only
partners, members or equity holders are one or more members of the

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Option Holder's "immediate family" and/or the Option Holder. Any Option held by
the transferee will continue to be subject to the same terms and conditions that
were applicable to the Option immediately prior to the transfer, except that the
Option will be transferable by the transferee only by will or the laws of
descent and distribution. For purposes hereof, "immediate family" means the
Option Holder's children, stepchildren, grandchildren, parents, stepparents,
grandparents, spouse, siblings (including half brothers and sisters), nieces,
nephews, in-laws, and relationships arising because of legal adoption.

          (k) Shareholders' Agreement. If this Option is exercised when the
Company is not a publicly-traded entity, simultaneous with the exercise of this
Option, the Option Holder shall, as a condition to the Option Holder's right to
exercise this Option, become a party to the Shareholders' Agreement by and among
the Company and its shareholders, as the same may be amended from time to time,
by execution of a joinder agreement in form and substance satisfactory to the
Company.

          (l) Restrictions on Transfer of Shares. Neither the Shares nor any
interest in them may be sold, assigned, pledged, hypothecated, encumbered or in
any other manner transferred or disposed of, in whole or in part, except in
compliance with the terms, conditions and restrictions as set forth in the
governing instruments of the Company, applicable United States federal and state
securities laws or other applicable laws or regulations and the terms and
conditions hereof.

          (m) Market Stand Off Period. The Option Holder covenants and agrees
that he or she shall not, without the prior written consent of the Company, sell
or otherwise dispose of any shares of stock of the Company during such period (a
"Market Stand Off Period") as the Company or its underwriters shall establish in
connection with the filing of a registration statement in connection with the
initial public offering of the stock of the Company (an "Initial Public
Offering").

          (n) Purchase Option. The Option Holder's Shares and Options are
subject to repurchase as provided below in subsections (i) through (vii) below:

               (i) If the Option Holder's active service with the Company or a
Subsidiary is terminated by the Option Holder other than for Good Reason (such
termination of active service shall be treated as occurring on the Notice Date)
or by the Company for Cause, the Company and/or its designee(s) shall have the
option (the "Purchase Option") to purchase, and if the Purchase Option is
exercised, the Grantor (as defined below) shall sell to the Company and/or its
assignee(s), all or any portion (at the Company's option) of the Shares and/or
Options held by the Grantor (such Shares and Options collectively being referred
to as the "Purchasable Shares").

               (ii) The Company shall give notice in writing to the Grantor of
the exercise of the Purchase Option within one (1) year after the Date of
Termination (as defined in the Employment Agreement) of the Option Holder's
service. Such notice shall state the number of Purchasable Shares to be
purchased by the Company and the determination of the purchase price of such
Purchasable Shares. If no notice is given within the time limit specified above,
the Purchase Option shall be deemed to have terminated.

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               (iii) The purchase price to be paid for the Purchasable Shares
purchased pursuant to the Purchase Option shall be, in the case of any Shares,
the Book Value (as defined below) per share as of the date of the notice of
exercise of the Purchase Option times the number of Shares being purchased, and
in the case of any Option, the Book Value per share (less the applicable per
share Option exercise price) times the number of vested Shares (including by
acceleration if applicable) subject to such Option which are being purchased by
the Company. The purchase price for the Purchasable Shares shall be paid in cash
or by wire transfer of immediately available funds. The closing of such purchase
shall take place at the Company's principal executive offices within ten (10)
days after the purchase price has been determined. At such closing, the Grantor
shall deliver to the purchaser(s) the certificates or instruments evidencing the
Purchasable Shares being purchased, duly endorsed (or accompanied by duly
executed stock powers) and otherwise in good form for delivery, against payment
of the purchase price by check of the purchaser(s). In the event that,
notwithstanding the foregoing, the Grantor shall have failed to obtain the
release of any pledge or other encumbrance on any Purchasable Shares by the
scheduled closing date, at the option of the purchaser(s) the closing shall
nevertheless occur on such scheduled closing date, with the cash purchase price
being reduced to the extent of, and paid to the holder of, all unpaid
indebtedness for which such Purchasable Shares are then pledged or encumbered.

               (iv) To ensure the enforceability of the Company's rights
hereunder, each certificate or instrument representing Shares or Options shall
bear a conspicuous legend in substantially the following form:

               "THE SHARES REPRESENTED BY THIS CERTIFICATE [ISSUABLE PURSUANT TO
               THIS AGREEMENT] ARE SUBJECT TO AN OPTION TO REPURCHASE PROVIDED
               UNDER THE PROVISIONS OF THE COMPANY'S 2005 LONG TERM INCENTIVE
               PLAN AND A STOCK OPTION AGREEMENT ENTERED INTO PURSUANT THERETO.
               A COPY OF SUCH LONG TERM INCENTIVE PLAN AND STOCK OPTION
               AGREEMENT ARE AVAILABLE UPON WRITTEN REQUEST TO THE COMPANY AT
               ITS PRINCIPAL EXECUTIVE OFFICES."

               (v) The Company's rights under this paragraph (n) shall terminate
upon the consummation of an Initial Public Offering.

               (vi) "Book Value" shall mean the book value of a Share at the end
of the fiscal quarter in which the termination of active service occurs (which,
in the case of termination by the Option Holder other than for Good Reason,
shall be treated as the Notice Date), as determined on a fully diluted basis by
the Board of Directors in good faith. Such determination shall be conclusive and
binding on all persons.

               (vii) "Grantor" shall mean, collectively, the Option Holder, the
Option Holder's assignee, the executor or the administrator of the Option
Holder's estate in the event of the Option Holder's death, and the Option
Holder's legal representative in the event of the Option Holder's incapacity.

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          (o) Forfeiture Upon Breach of Certain Other Agreements. The Option
Holder's breach of any noncompete, nondisclosure, nonsolicitation, assignment of
inventions, or other intellectual property agreement that he may be a party to
with the Company or a Subsidiary, in addition to whatever other equitable relief
or monetary damages that the Company or a Subsidiary may be entitled to, shall
result in automatic rescission, forfeiture, cancellation, and return of any
Options and Shares (whether or not otherwise vested) held by Optionee or
Grantor, and all profits, proceeds, gains, or other consideration received
through the sale or other transfer of the Options or Shares shall be promptly
returned and repaid to the Company.

          (p) Withholding. The Option Holder agrees to make appropriate
arrangements with the Company for satisfaction of any applicable tax withholding
requirements, or similar requirements, arising out of this Agreement.

          (q) References. References herein to rights and obligations of the
Option Holder shall apply where appropriate, to the Option Holder's legal
representative or estate without regard to whether specific reference to such
legal representative or estate is contained in a particular provision of this
Agreement.

          (r) Notice. Any notice required or permitted to be given under this
Agreement shall be in writing and shall be deemed to have been given when
delivered personally or by courier, or sent by certified or registered mail,
postage prepaid, return receipt requested, duly addressed to the party concerned
at the address indicated below or to such changed address as such party may
subsequently by similar process given notice of:

               If to the Company:

               Validus Holdings, Ltd.
               Mintflower Place
               8 Par-La-Ville Road, Third Floor
               Hamilton HMO8 Bermuda

               Attention: Chief Financial Officer

               If to the Option Holder:

               At the Option Holder's most recent address shown on the Company's
               corporate records, or at any other address which the Option
               Holder may specify in a notice to the Company delivered in the
               manner set forth herein.

          (s) Governing Law. This Agreement shall be governed by and construed
in accordance with the laws of Bermuda, without giving effect to principles of
conflict of laws.

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          (t) Counterparts. This Agreement may be executed in multiple
counterparts, each of which shall be regarded for all purposes as an original
constituting but one and the same instrument.

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          IN WITNESS WHEREOF, the undersigned have executed this Agreement as of
the date first written above.

                                        VALIDUS HOLDINGS, LTD.


                                        By:
                                            ------------------------------------
                                        Name: George Reeth
                                        Title: President


                                        ----------------------------------------
                                        EDWARD NOONAN