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                                                                   EXHIBIT 10.31

                       INVESTORS FINANCIAL SERVICES CORP.

                      NON-QUALIFIED STOCK OPTION AGREEMENT

       Investors Financial Services Corp., a Delaware corporation (the
"Company"), hereby grants as of the 15th day of November, 2004 to Robert D.
Mancuso (the "Optionee"), an option to purchase a maximum of 111,294 shares (the
"Option Shares") of its Common Stock, $.01 par value ("Common Stock"), at the
price of $41.03 per share, on the following terms and conditions:

       1.     GRANT UNDER 1995 STOCK OPTION PLAN. This option is granted
pursuant to and is governed by the Company's 1995 Stock Plan (the "Plan") and,
unless the context otherwise requires, terms used herein shall have the same
meaning as in the Plan. Determinations made in connection with this option
pursuant to the Plan shall be governed by the Plan as it exists on this date.

       2.     GRANT AS NON-QUALIFIED OPTION; OTHER OPTIONS. This option shall be
treated for federal income tax purposes as a Non-Qualified Option (rather than
an incentive stock option). This option is in addition to any other options
heretofore or hereafter granted to the Optionee by the Company or any Related
Corporation (as defined in the Plan), but a duplicate original of this
instrument shall not effect the grant of another option.

       3.     VESTING OF OPTION IF BUSINESS RELATIONSHIP CONTINUES. The option
granted pursuant to this Agreement is fully vested. While the Optionee continues
to maintain a Business Relationship with the Company or any Related Corporation,
the option granted pursuant to this Agreement may be exercised up to and
including the date of November 15, 2014.

       4.     TERM AND TERMINATION OF OPTION RIGHTS.

              (a)    TERMINATION OTHER THAN FOR CAUSE: If the Optionee's
Business Relationship with the Company and all Related Corporations is
terminated, other than by reason of death, disability or dissolution as defined
in Section 5 or termination for Cause as defined in Section 4(c), no further
installments of this option shall become exercisable, and this option shall
terminate after the passage of three (3) months from the date the Business
Relationship ceases, but in no event later than the scheduled expiration date.
In such a case, the Optionee's only rights hereunder shall be those which are
properly exercised before the termination of this option.

              (b)    TERMINATION FOR CAUSE: If the Optionee's Business
Relationship with the Company is terminated for Cause (as defined in Section
4(c)), this option shall terminate upon the Optionee's receipt of written notice
of such termination and shall thereafter not be exercisable to any extent
whatsoever.

              (c)    DEFINITION OF CAUSE: "Cause" shall mean conduct involving
one or more of the following: (i) the substantial and continuing failure of the
Optionee, after notice thereof, to render services to the Company or Related
Corporation in accordance with the terms or requirements of the Optionee's
Business Relationship with the Company; (ii) disloyalty, gross negligence,
willful misconduct, dishonesty or breach of fiduciary duty to the Company or
Related Corporation; (iii) the commission of an act of embezzlement or fraud;
(iv) deliberate disregard of the rules or policies of the Company or Related
Corporation which results in direct or indirect loss, damage or injury to the
Company or Related Corporation; (v) the unauthorized disclosure of any trade
secret or confidential information of the Company or Related Corporation; or
(vi) the commission of an act which constitutes


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unfair competition with the Company or Related Corporation or which induces any
customer or supplier to break a contract with the Company or Related
Corporation.

       5.     DEATH; DISABILITY; DISSOLUTION.

              (a)    DEATH: If the Optionee is a natural person who dies while
involved in a Business Relationship with the Company, this option may be
exercised, to the extent otherwise exercisable on the date of his or her death,
by the Optionee's estate, personal representative or beneficiary to whom this
option has been assigned pursuant to Section 9, at any time within one year
after the date of death, but not later than the scheduled expiration date.

              (b)    DISABILITY: If the Optionee is a natural person whose
Business Relationship with the Company is terminated by reason of his or her
disability (as defined in the Plan), this option may be exercised, to the extent
otherwise exercisable on the date the Business Relationship was terminated, at
any time within one year after such termination, but not later than the
scheduled expiration date.

              (c)    EFFECT OF TERMINATION: At the expiration of such one year
period provided in paragraph (a) or (b) of this Section 5 or the scheduled
expiration date, whichever is the earlier, this option shall terminate and the
only rights hereunder shall be those as to which the option was properly
exercised before such termination.

              (d)    DISSOLUTION: If the Optionee is a corporation, partnership,
trust or other entity that is dissolved, is liquidated, becomes insolvent or
enters into a merger or acquisition with respect to which the Optionee is not
the surviving entity, at a time when the Optionee is involved in a Business
Relationship with the Company, this option shall immediately terminate as of the
date of such event, and the only rights hereunder shall be those as to which
this option was properly exercised before such dissolution or other event.

       6.     PARTIAL EXERCISE. This option may be exercised in part at any time
and from time to time within the above limits, except that this option may not
be exercised for a fraction of a share unless such exercise is with respect to
the final installment of stock subject to this option and cash in lieu of a
fractional share must be paid, in accordance with Paragraph 13(G) of the Plan,
to permit the Optionee to exercise completely such final installment. Any
fractional share with respect to which an installment of this option cannot be
exercised because of the limitation contained in the preceding sentence shall
remain subject to this option and shall be available for later purchase by the
Optionee in accordance with the terms hereof.

       7.     PAYMENT OF PRICE.

              (a)    FORM OF PAYMENT: The option price shall be paid in the
following manner:

                  (i)   in United States dollars in cash, or by check;

                 (ii)   subject to paragraph 7(b) below, through delivery of
                        shares of the Company's Common Stock having a fair
                        market value (as determined by the Committee) equal as
                        of the date of exercise to the cash exercise price of
                        options;

                (iii)   by delivery of an assignment satisfactory in form and
                        substance to the Company of a sufficient amount of the
                        proceeds from the sale of the Common Stock and an
                        instruction to the broker or selling agent to pay that
                        amount to the Company; or


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                 (iv)   at the discretion of the Committee, any combination of
                        (i), (ii), and (iii) above.

              (b)    LIMITATIONS ON PAYMENT BY DELIVERY OF COMMON STOCK: If the
Optionee delivers Common Stock held by the Optionee ("Old Stock") to the Company
in full or partial payment of the option price, and the Old Stock so delivered
is subject to restrictions or limitations imposed by agreement between the
Optionee and the Company, an equivalent number of Option Shares shall be subject
to all restrictions and limitations applicable to the Old Stock to the extent
that the Optionee paid for the Option Shares by delivery of Old Stock, in
addition to any restrictions or limitations imposed by this Agreement.
Notwithstanding the foregoing, the Optionee may not pay any part of the exercise
price hereof by transferring Common Stock to the Company unless such Common
Stock has been owned by the Optionee free of any substantial risk of forfeiture
for at least six months.

              (c)    RELOAD OPTION GRANTS: If an Optionee makes payment for the
exercise of an option granted hereunder through the delivery to the Company of
shares of the Company's Common Stock pursuant to paragraph 7(a)(ii) of this
Agreement, such Optionee shall be granted automatically a new "reload" stock
option. Such new "reload" stock option shall (i) be a non-qualified option to
purchase the number of shares provided as consideration for the exercise price
in connection with the exercise of the original stock option, (ii) have a per
share exercise price equal to the fair market value of such shares as of the
date of exercise of the original stock option, (iii) be immediately exercisable
and have a term of ten years from the date of the original stock option, and
(iv) otherwise have the same terms and conditions as the original stock option,
except that it will not provide for the automatic grant of additional reload
stock options upon its exercise.

       8.     METHOD OF EXERCISING OPTION. Subject to the terms and conditions
of this Agreement, this option may be exercised by written notice to the
Company, at the principal executive office of the Company, or to such transfer
agent as the Company shall designate. Such notice shall state the election to
exercise this option and the number of Option Shares for which it is being
exercised and shall be signed by the person or persons so exercising this
option. Such notice shall be accompanied by payment of the full purchase price
of such shares, and the Company shall deliver a certificate or certificates
representing such shares as soon as practicable after the notice shall be
received. Such certificate or certificates shall be registered in the name of
the person or persons so exercising this option (or, if this option shall be
exercised by the Optionee and if the Optionee shall so request in the notice
exercising this option, shall be registered in the name of the Optionee and
another person jointly, with right of survivorship). In the event this option
shall be exercised, pursuant to Section 5 hereof, by any person or persons other
than the Optionee, such notice shall be accompanied by appropriate proof of the
right of such person or persons to exercise this option.

       9.     OPTION NOT TRANSFERABLE. This option is not transferable or
assignable except (i) by will or by the laws of descent and distribution, (ii)
pursuant to a valid domestic relations order or (iii) to, or for the benefit of,
family members or to other persons for estate planning purposes. . During the
Optionee's lifetime, only the Optionee can exercise this option (or, if the
Optionee is a natural person and is disabled and so long as this option remains
exercisable, by the Optionee's duly appointed guardian or other legal
representative).

       10.    NO OBLIGATION TO EXERCISE OPTION. The grant and acceptance of this
option imposes no obligation on the Optionee to exercise it.


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       11.    NO OBLIGATION TO CONTINUE BUSINESS RELATIONSHIP. Neither the Plan,
this Agreement, nor the grant of this option imposes any obligation on the
Company or any Related Corporation to continue to maintain a Business
Relationship with the Optionee.

       12.    NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have
no rights as a stockholder with respect to the Option Shares until such time as
the Optionee has exercised this option by delivering a notice of exercise and
has paid in full the purchase price for the number of shares for which this
option is to be so exercised in accordance with Section 8. Except as is
expressly provided in the Plan with respect to certain changes in the
capitalization of the Company, no adjustment shall be made for dividends or
similar rights for which the record date is prior to such date of exercise.

       13.    CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains
provisions covering the treatment of options in a number of contingencies such
as stock splits and mergers. Provisions in the Plan for adjustment with respect
to stock subject to options and the related provisions with respect to
successors to the business of the Company are hereby made applicable hereunder
and are incorporated herein by reference.

       14.    WITHHOLDING TAXES. If the Company or any Related Corporation in
its discretion determines that it is obligated to withhold any tax in connection
with the exercise of this option, or in connection with the transfer of, or the
lapse of restrictions on, any Common Stock or other property acquired pursuant
to this option, the Optionee hereby agrees that the Company or any Related
Corporation may withhold from the Optionee's wages or other remuneration the
appropriate amount of tax. At the discretion of the Company or Related
Corporation, the amount required to be withheld may be withheld in cash from
such wages or other remuneration or in kind from the Common Stock or other
property otherwise deliverable to the Optionee on exercise of this option. The
Optionee further agrees that, if the Company or Related Corporation does not
withhold an amount from the Optionee's wages or other remuneration sufficient to
satisfy the withholding obligation of the Company or Related Corporation, the
Optionee will make reimbursement on demand, in cash, for the amount
underwithheld.

       15.    ARBITRATION. Any dispute, controversy, or claim arising out of, in
connection with, or relating to the performance of this Agreement or its
termination shall be settled by arbitration in the Commonwealth of
Massachusetts, pursuant to the rules then obtaining of the American Arbitration
Association. Any award shall be final, binding and conclusive upon the parties
and a judgment rendered thereon may be entered in any court having jurisdiction
thereof.

       16.    PROVISION OF DOCUMENTATION TO EMPLOYEE. By signing this Agreement
the Optionee acknowledges receipt of a copy of this Agreement and a copy of the
Plan.

       17.    MISCELLANEOUS.

              (a)    NOTICES: All notices hereunder shall be in writing and
shall be deemed given when sent by certified or registered mail, postage
prepaid, return receipt requested, to the address set forth below. The addresses
for such notices may be changed from time to time by written notice given in the
manner provided for herein.

              (b)    ENTIRE AGREEMENT; MODIFICATION: This Agreement constitutes
the entire agreement between the parties relative to the subject matter hereof,
and supersedes all proposals, written or oral, and all other communications
between the parties relating to the subject matter of this Agreement. This
Agreement may be modified, amended or rescinded only by a written agreement
executed by both parties.


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              (c)    SEVERABILITY: The invalidity, illegality or
unenforceability of any provision of this Agreement shall in no way affect the
validity, legality or enforceability of any other provision.

              (d)    SUCCESSORS AND ASSIGNS: This Agreement shall be binding
upon and inure to the benefit of the parties hereto and their respective
successors and assigns, subject to the limitations set forth in Section 9
hereof.

              (e)    GOVERNING LAW: This Agreement shall be governed by and
interpreted in accordance with the laws of the Commonwealth of Massachusetts,
without giving effect to the principles of the conflicts of laws thereof. The
preceding choice of law provision shall apply to all claims, under any theory
whatsoever, arising out of the relationship of the parties contemplated herein.


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       IN WITNESS WHEREOF, the Company and the Optionee have caused this
instrument to be executed as of the date first above written.

                                       Investors Financial Services Corp.
                                       200 Clarendon Street
/S/ ROBERT D. MANCUSO                  Boston, MA 02116
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Employee

ROBERT D. MANCUSO                      By: /s/ JOHN N. SPINNEY, JR.
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Print Name of Employee

                                       JOHN N. SPINNEY, JR.
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Street Address                         Name

                                       SENIOR VP AND CHIEF FINANCIAL OFFICER
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City         State       Zip Code      Title


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