<PAGE>

                                                                    EXHIBIT 4.12

                  UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR
SECURITIES OF THIS SERIES IN CERTIFICATED FORM, THIS SECURITY MAY NOT BE
TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY
OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE
DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR
A NOMINEE OF SUCH DEPOSITARY. UNLESS THIS CERTIFICATE IS PRESENTED BY AN
AUTHORIZED REPRESENTATIVE OF SUCH A TRANSFEROR TO THE ISSUER OR ITS AGENT FOR
REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS
REGISTERED IN THE NAME OF SUCH A TRANSFEREE OR SUCH OTHER NAME AS REQUESTED BY
AN AUTHORIZED REPRESENTATIVE OF SUCH A TRANSFEROR AND ANY PAYMENT IS MADE TO
SUCH A TRANSFEREE, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR
OTHERWISE BY OR TO ANY PERSON IS WRONGFUL SINCE THE REGISTERED OWNER HEREOF,
SUCH A TRANSFEROR, HAS AN INTEREST HEREIN.

                  THESE SECURITIES ARE NOT SAVINGS OR DEPOSIT ACCOUNTS AND ARE
NOT INSURED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION OR ANY OTHER
GOVERNMENTAL AGENCY.

REGISTERED                                                            REGISTERED
No.-1-                                                              $100,000,000
CUSIP: 585515 AD 1                                           [x] GLOBAL SECURITY

                           MELLON FUNDING CORPORATION
                         5% SUBORDINATED NOTES DUE 2014

                  Mellon Funding Corporation, a corporation duly organized and
existing under the laws of the Commonwealth of Pennsylvania (herein called the
"Company", which term includes any successor corporation under the Indenture
hereinafter referred to), for value received, hereby promises to pay to Cede &
Co., or registered assigns, the principal sum of ONE HUNDRED MILLION DOLLARS
($100,000,000) on December 1, 2014, and to pay interest thereon from June 1,
2003, or from the most recent Interest Payment Date to which interest has been
paid or duly provided for, semi-annually on June 1 and December 1 in each year,
commencing December 1, 2003, at the rate of 5% per annum, and (to the extent
that the payment of such interest shall be legally enforceable) at the rate of
5% per annum on any overdue principal and premium and on any overdue installment
of interest. The interest so payable, and punctually paid or

<PAGE>

duly provided for, on any Interest Payment Date will, as provided in such
Indenture, be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on the Regular
Record Date for such interest, which shall be the May 15 or November 15 whether
or not a Business Day), as the case may be, next preceding such Interest Payment
Date. Any such interest not so punctually paid or duly provided for will
forthwith cease to be payable to the Holder on such Regular Record Date and may
either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date for the payment of such Defaulted Interest to be fixed by the
Trustee, notice whereof shall be given to Holders of Securities of this series
not less than 10 days prior to such Special Record Date, or be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities of this series may be listed, and
upon such notice as may be required by such exchange, all as more fully provided
in said Indenture.

                  If this Security is a Global Security (as specified on the
face hereof), this Security is exchangeable in whole for definitive Securities
of this series in registered form ("Registered Securities") of like tenor and of
an equal aggregate principal amount only if (i) the Depositary notifies the
Company that it is unwilling or unable or no longer qualifies to continue as
Depositary for this Global Security and the Company does not appoint another
institution to act as Depositary, (ii) the Company executes and delivers to the
Trustee a Company Order providing that this Global Security shall be
exchangeable for definitive Registered Securities or (iii) any event shall have
happened and be continuing which, after notice or lapse of time, or both, would
become an Event of Default with respect to the Securities of the series of which
this Global Security is a part. In the event this Global Security is
exchangeable pursuant to the preceding sentence, it shall be exchanged in whole
for definitive Registered Securities of this series, of like tenor and of an
equal aggregate principal amount in denominations of U.S. $1,000 and integral
multiples thereof; provided that, in the case of clauses (ii) and (iii) above,
definitive Registered Securities of this series will be issued in exchange for
this Global Security only if such definitive Registered Securities were
requested by written notice to the Security Registrar by or on behalf of a
Person who is a beneficial owner of an interest herein given through the Holder
hereof. Any definitive Registered Securities of this series issued in exchange
for this Global Security shall be registered in

                                      -2-

<PAGE>

the name or names of such Person or Persons as the Holder hereof shall instruct
the Security Registrar. Except as provided above, owners of beneficial interests
in this Global Security will not be entitled to receive physical delivery of
Securities in definitive form and will not be considered the Holders thereof for
any purpose under the Indenture.

                  If this Security is a Global Security, except as provided in
the next paragraph, no beneficial owner of any portion of this Global Security
shall be entitled to receive payment of accrued interest hereon until this
Global Security has been exchanged for one or more definitive Registered
Securities of this series, as provided herein and in the Indenture.

                  If this Security is a Global Security and if a definitive
Registered Security or Registered Securities of this series are issued in
exchange for this Global Security after the close of business at the office or
agency where such exchange occurs on (i) any Regular Record Date and before the
opening of business at such office or agency on the related Interest Payment
Date, or (ii) any Special Record Date and before the opening of business at such
office or agency on the related proposed date for payment of Defaulted Interest
or interest on Defaulted Interest, as the case may be, accrued interest will not
be payable on such Interest Payment Date or proposed date for payment, as the
case may be, in respect of such Registered Security, but will be payable on such
Interest Payment Date or proposed date for payment, as the case may be, only to
the Holder hereof, and the Holder hereof will undertake in such circumstances to
credit such interest to the account or accounts of the Persons who were the
beneficial owners of any portion of this Global Security on such Regular Record
Date or Special Record Date, as the case may be.

                  If this Security is a Global Security, payment of the
principal of and any premium or interest hereon will be made on each Interest
Payment Date and at the Maturity Date, as the case may be, by the Trustee by
wire transfer of immediately available funds, in such coin or currency of the
United States of America as at the time of payment is legal tender for payment
of public and private debts, to an account of the registered Holder hereof at
the Federal Reserve Bank of New York, provided, that, payment at the Maturity
Date hereof shall be made against presentation of this Security at the office of
the Trustee, currently located at 1 Bank One Plaza, Chicago, IL 60670.

                                      -3-

<PAGE>

                  If this Security is not a Global Security, (i) the principal
of and any interest and premium hereon payable at the Maturity Date hereof will
be paid in immediately available funds, in such coin or currency of the United
States of America as at the time of payment is legal tender for payment of
public and private debts, against presentation of this Security at the
aforementioned office of the Trustee, and (ii) all interest payments hereon
other than interest due at the Maturity Date hereof will be made by check drawn
on the Trustee and mailed by the Trustee to the person entitled thereto as
provided herein, provided, that Holders of $10,000,000 or more in aggregate
principal amount of Securities of this series shall be entitled to receive such
payments by wire transfer of immediately available funds if appropriate wire
transfer instructions have been received in writing by the Trustee not less than
16 days prior to the applicable Interest Payment Date.

                  Reference is hereby made to the further provisions of this
Security set forth on the reverse hereof, which further provisions shall for all
purposes have the same effect as if set forth at this place.

                  This Security is not a deposit and is not insured by any
federal agency.

                  Unless the certificate of authentication hereon has been
executed by the Trustee referred to on the reverse hereof, or an Authenticating
Agent, by manual signature, neither this Security nor the Guarantee endorsed
hereon shall be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

                                      -4-

<PAGE>

                  IN WITNESS WHEREOF, the Company has caused this instrument to
be duly executed under its corporate seal.

                                           MELLON FUNDING CORPORATION

                                           By: /S/ MICHAEL A. BRYSON
                                               Name:  Michael A. Bryson
                                               Title: President & Chief
                                                      Executive Officer

Attest:

/S/ MICHAEL J. BAKER

Secretary

Dated: June 19, 2003

CERTIFICATE OF AUTHENTICATION
This is one of the Securities of the
series designated herein referred to
in the within-mentioned Indenture.

BANK ONE TRUST COMPANY, N.A.
    as Trustee

By:   /S/ LAWRENCE DILLARD
   -------------------------
      Authorized Officer

                                      -5-

<PAGE>

                  This Security is one of a duly authorized series of Securities
of the Company (herein called the "Securities"), of the series hereinafter
specified, issued and to be issued under an Indenture, dated as of June 12,
2000, as supplemented by the First Supplemental Indenture, dated as of April 30,
2001 (herein called the "Indenture"), among the Company, the Guarantor and Bank
One Trust Company, N.A., as Trustee (herein called the "Trustee", which term
includes any successor trustee under the Indenture), to which Indenture and all
indentures supplemental thereto reference is hereby made for a statement of the
respective rights, limitations of rights, duties and immunities thereunder of
the Company, the Guarantor, the Trustee, the Holders of the Senior Indebtedness
of the Company and the Guarantor and the Holders of the Securities and of the
terms upon which the Securities are, and are to be, authenticated and delivered.
The Securities may be issued in different series, as in the Indenture provided.
This Security is one of the series designated on the face hereof, issued under
and entitled to the benefits of the Indenture and issued in an aggregate
principal amount of $100,000,000.

                  The Securities of this series are redeemable at the option of
the Company, upon not less than 30 days nor more than 60 days' notice by mail,
at any time, at a Redemption Price equal to the greater of (i) 100% of the
principal amount of the Securities redeemed or (ii) the sum of the present
values of the Remaining Scheduled Payments on this Security, discounted to such
redemption date on a semiannual basis, assuming a 360-day year consisting of
twelve 30-day months, at the Treasury Rate plus 20 basis points. In either case,
the Redemption Price shall also include interest accrued to the date of
redemption on the principal balance of this Security to be redeemed.

                  "Treasury Rate" means an annual rate equal to the semiannual
                  equivalent yield to maturity of the Comparable Treasury Issue
                  (as defined below), assuming a price for the Comparable
                  Treasury Issue (expressed as a percentage of its principal
                  amount) equal to the Comparable Treasury Price for the
                  redemption date. The semiannual equivalent yield to maturity
                  will be computed as of the second Business Day immediately
                  preceding the redemption date.

                  "Comparable Treasury Issue" means the United States Treasury
                  security selected by an independent investment banking firm
                  that would be

                                      -6-

<PAGE>

                  used, at the time of selection and in accordance with
                  customary financial practice, in pricing new issues of
                  corporate debt securities of comparable maturity to the
                  remaining term of the Securities. The term "independent
                  investment banking firm" means one of the Reference Treasury
                  Dealers that the Company appoints.

                  "Comparable Treasury Price" means, with respect to any
                  redemption date, (i) the average of the bid and asked prices
                  for the Comparable Treasury Issue (expressed in each case as a
                  percentage of its principal amount) on the third Business Day
                  preceding such redemption date, as set forth in the daily
                  statistical release (or any successor release) published by
                  the Federal Reserve Bank of New York and designated "Composite
                  3:30 p.m. Quotations for U.S. Government Securities" or (ii)
                  if such release (or any successor release) is not published or
                  does not contain such prices on such business day, (A) the
                  average of the Reference Treasury Dealer Quotations for such
                  redemption date, after excluding the highest and lowest of
                  such Reference Treasury Dealer Quotations, or (B) if the
                  Trustee obtains fewer than four such Reference Treasury Dealer
                  Quotations, the average of all such Quotations.

                  "Reference Treasury Dealer" means each of Credit Suisse First
                  Boston LLC (and its successors), and any three other
                  nationally recognized investment banking firms that the
                  Company shall appoint from time to time that are primary
                  dealers of U.S. government securities in New York City (each,
                  a "Reference Treasury Dealer"). If any of the firms named in
                  the preceding sentence ceases to be a primary dealer of U.S.
                  government securities in New York City, the Company shall
                  appoint another nationally recognized investment banking firm
                  as a substitute.

                  "Reference Treasury Dealer Quotation" means, with respect to
                  any Redemption Date, the average, as determined by the
                  Trustee, of the bid and asked prices for the Comparable
                  Treasury Issue, expressed in each case as a percentage of its
                  principal amount, quoted in writing to the Trustee by a
                  Reference Treasury Dealer as of 3:30 p.m., New York time, on
                  the third Business Day preceding that redemption date. The
                  Trustee shall seek Reference Treasury Dealer Quotations in
                  respect of

                                      -7-

<PAGE>

                  any Redemption Date from each of the then-existing Reference
                  Treasury Dealers.

                  "Remaining Scheduled Payments" means, with respect to each
                  Security being redeemed, the remaining scheduled payments of
                  principal and interest on that Security that would be due
                  after the related Redemption Date but for the redemption. If,
                  however, the Redemption Date is not an Interest Payment Date
                  with respect to that Security, the amount of the next
                  succeeding scheduled interest payment on that Security that
                  would have been due will be deemed reduced by the amount of
                  interest accrued on the Security to the redemption date.

                  The Company reserves the right from time to time, without
notice to or the consent of the Holders of the Securities, to create and issue
further notes ranking equally and ratably with the Securities in all respects,
or in all respects except for the payment of interest accruing prior to the
issue date or except for the first payment of interest following the issue date
of those further securities. Any further securities will be consolidated and
form a single series with the Securities and will have the same terms as to
status, redemption or otherwise as the Securities. Any further securities may be
issued pursuant to a resolution of the board of directors of the Company, a
supplement to the Indenture, or under an officers' certificate pursuant to the
Indenture.

                  If an Event of Default with respect to Securities of this
series shall occur and be continuing, the principal of the Securities of this
series may be declared due and payable in the manner and with the effect
provided in the Indenture. Upon payment (i) of the amount of principal so
declared due and payable and (ii) of interest on any overdue principal and
overdue interest (in each case to the extent that the payment of such interest
shall be legally enforceable), all of the Company's obligations in respect of
the payment of the principal of and interest on the Securities of this series
shall terminate.

                  The indebtedness evidenced by this Security is, to the extent
provided in the Indenture, subordinate and subject in right of payment to the
prior payment in full of all Senior Indebtedness of the Company, and this
Security is issued subject to the provisions of the Indenture with respect
thereto. Each Holder of this Security, by accepting the same, (a) agrees to and
shall be bound by such provisions, (b) authorizes and directs the Trustee on his
behalf to take such action as may be necessary or

                                      -8-

<PAGE>

appropriate to effectuate the subordination so provided and (c) appoints the
Trustee his attorney-in-fact for any and all such purposes.

                  The Indenture permits, with certain exceptions as therein
provided, the amendment thereof and the modification of the rights and
obligations of the Company and the Guarantor and the rights of the Holders of
the Securities of each series to be affected under the Indenture at any time by
the Company, the Guarantor and the Trustee with the consent of the Holders of
not less than 66 2/3% in aggregate principal amount of the Securities at the
time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in aggregate
principal amount of the Securities of each series at the time Outstanding, on
behalf of the Holders of all Securities of such series, to waive compliance by
the Company or the Guarantor with certain provisions of the Indenture and
certain past defaults under the Indenture and their consequences. Any such
consent or waiver by the Holder of this Security shall be conclusive and binding
upon such Holder and upon all future Holders of this Security and of any
Security issued upon the registration of transfer hereof or in exchange herefor
or in lieu hereof, whether or not notation of such consent or waiver is made
upon this Security.

                  The Guarantor, or a Subsidiary thereof, may directly assume,
by a supplemental indenture, the due and punctual payment of the principal of
(and premium, if any) and interest on all the Securities, in which case the
Company shall be released from its liability as obligor on the Securities.

                  No reference herein to the Indenture and no provision of this
Security or of the Indenture shall alter or impair the obligation of the
Company, which is absolute and unconditional, to pay the principal of (and
premium, if any) and interest on this Security at the times, places and rate,
and in the coin or currency, herein prescribed.

                  As provided in the Indenture and subject to certain
limitations therein set forth, the transfer of this Security is registrable in
the Security Register, upon surrender of this Security for registration of
transfer at the office or agency of the Company, in the place referred to on the
face hereof, where the principal of (and premium, if any) and interest on this
Security are payable, duly endorsed by, or accompanied by a written instrument
of transfer in form satisfactory to the Company and the Security Registrar duly
executed by, the Holder hereof or

                                      -9-

<PAGE>

his attorney duly authorized in writing, and thereupon one or more new
Securities of this series and of like tenor, of authorized denominations and for
the same aggregate principal amount, will be issued to the designated transferee
or transferees.

                  The Securities of this series are issuable only in registered
form without coupons in denominations of $1,000 and any integral multiple
thereof. As provided in the Indenture and subject to certain limitations therein
set forth, Securities of this series are exchangeable for a like aggregate
principal amount of Securities of this series and of like tenor and of a
different authorized denomination, as requested by the Holder surrendering the
same.

                  No service charge shall be made for any such registration of
transfer or exchange, but the Company may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

                  Prior to due presentment of this Security for registration of
transfer, the Company, the Guarantor and the Trustee and any agent of the
Company, the Guarantor or the Trustee may treat the Person in whose name this
Security is registered as the owner hereof for all purposes, whether or not this
Security be overdue, and neither the Company, the Guarantor, the Trustee nor any
such agent shall be affected by notice to the contrary.

                  All terms used in this Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

                                      -10-

<PAGE>

                                  ABBREVIATIONS

                  The following abbreviations, when used in the inscription on
the face of this instrument, shall be construed as though they were written out
in full according to applicable laws or regulations.

                  TEN COM -- as tenants in common

                  TEN ENT -- as tenants by the entireties

                  JT TEN  -- as joint tenants with right of
                             survivorship and not as tenants in
                             common

                  UNIF GIFT MIN ACT--__________Custodian_________
                                       (Cust)            (Minor)

                        Under Uniform Gifts to Minors Act

                        _________________________________
                               (State)

                  Additional abbreviations may also be used though not in the
above list.

                                      -11-

<PAGE>

                  FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s)
and transfer(s) unto

Please Insert Social Security or Other
         Identifying Number of Assignee:

________________________________________________________________________________

________________________________________________________________________________

PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS
INCLUDING ZIP CODE OF ASSIGNEE:

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

the within Security and all rights thereunder, hereby irrevocably constituting
and appointing ________________ attorney to transfer said Security on the
Security Register of the Company, with full power of substitution in the
premises.

Dated: ______________________              _____________________________________
                                           NOTICE: The signature to this
                                           assignment must correspond with the
                                           name as written upon the face of
                                           this Security in every particular,
                                           without alteration or enlargement
                                           or any change whatever.

                                      -12-

<PAGE>

                                    GUARANTEE

                                       OF

                          MELLON FINANCIAL CORPORATION

                  For value received, Mellon Financial Corporation, a
corporation duly organized and existing under the laws of the Commonwealth of
Pennsylvania (herein called the "Guarantor"), hereby unconditionally guarantees
to the Holder of the Security upon which this Guarantee is endorsed the due and
punctual payment of the principal of (and premium, if any) and interest on said
Security, when and as the same shall become due and payable, whether at
maturity, by acceleration or redemption or otherwise, according to the terms
thereof and of the Indenture referred to therein. In case of the failure of
Mellon Funding Corporation or any successor thereto (the "Company") punctually
to pay any such principal, premium or interest, the Guarantor hereby agrees to
cause any such payment to be made punctually when and as the same shall become
due and payable, whether at maturity, upon acceleration or redemption or
otherwise, and as if such payment were made by the Company.

                  The Guarantor hereby agrees that its obligations hereunder
shall be as principal and not merely as surety, and shall be absolute and
unconditional, irrespective of, and shall be unaffected by, any invalidity,
irregularity or unenforceability of said Security or said Indenture, any failure
to enforce the provisions of said Security or said Indenture, or any waiver,
modification, consent or indulgence granted to the Company with respect thereto,
by the Holder of said Security or the Trustee under said Indenture, the recovery
of any judgment against the Company or any action to enforce the same, or any
other circumstances which may otherwise constitute a legal or equitable
discharge of a surety or guarantor. The Guarantor hereby waives diligence,
presentment, demand of payment, filing of claims with a court in the event of
merger, insolvency or bankruptcy of the Company, any right to require a
proceeding first against the Company, protest or notice with respect to said
Security or the indebtedness evidenced thereby and all demands whatsoever, and
covenants that this Guarantee will not be discharged except by payment in full
of the principal, and premium, if any, and interest on said Security and the
complete performance of all other obligations contained in said Security.

                  The Guarantor shall be subrogated to all rights of the Holder
of said Security against the Company in respect

                                      -13-

<PAGE>

of any amounts paid to such Holder by the Guarantor pursuant to the provisions
of this Guarantee; provided, however, that the Guarantor shall not be entitled
to enforce, or to receive any payments arising out of or based upon, such right
of subrogation until the principal of (and premium, if any) and interest on all
Securities issued under said Indenture shall have been paid in full.

                  Subject to the next following paragraph, the Guarantor hereby
certifies and warrants that all acts, conditions and things required to be done
and performed and to have happened precedent to the creation and issuance of
this Guarantee and to constitute the same the valid obligation of the Guarantor
have been done and performed and have happened in due compliance with all
applicable laws.

                  Claims under the Guarantee are, to the extent provided in the
Indenture, subordinate and subject in right of payment to the prior payment in
full of all Senior Indebtedness of the Guarantor, and this Guarantee is issued
subject to the provisions of the Indenture with respect thereto. Each Holder of
a Security upon which this Guarantee is endorsed, by accepting the same, (a)
agrees to and shall be bound by such provisions, (b) authorizes and directs the
Trustee on his behalf to take such action as may be necessary or appropriate to
effectuate the subordination so provided and (c) appoints the Trustee his
attorney-in-fact for any and all such purposes.

                  This Guarantee shall not be valid or become obligatory for any
purpose until the certificate of authentication on said Security shall have been
signed manually by or on behalf of the Trustee under said Indenture.

                  This Guarantee shall be deemed to be a contract made under the
laws of the Commonwealth of Pennsylvania, and for all purposes shall be governed
by and construed in accordance with the laws of the Commonwealth of
Pennsylvania, except as otherwise required by mandatory provisions of law.

                                      -14-

<PAGE>

                  IN WITNESS WHEREOF, the Guarantor has caused this Guarantee to
be duly executed under its corporate seal.

                                           MELLON FINANCIAL CORPORATION

                                           By:   /S/ MICHAEL A. BRYSON
                                              Name:  Michael A. Bryson
                                              Title: Executive Vice
                                                     President & Chief
                                                     Financial Officer
Attest:

/S/ CARL KRASIK

Name:  Carl Krasik
Title: Secretary

Dated: June 19, 2003

                                      -15-