Exhibit 4.3


                               30th March, 2001



                     CIBA SPECIALTY CHEMICALS HOLDING INC.
                                 as Guarantor







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                               DEED OF GUARANTEE

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                                ALLEN & OVERY
                                    London


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                               DEED OF GUARANTEE

THIS DEED OF GUARANTEE is made on 30th March, 2001 by CIBA SPECIALTY CHEMICALS
HOLDING INC., (the "Guarantor") in favour of the Relevant Account Holders (as
defined in the Deed of Covenant referred to below) and the holders for the
time being of the Notes (as defined below) and the interest coupons (if any)
appertaining to the Notes ("Coupons"), the Coupons being attached on issue to
Definitive Note(s) (as defined below). Each Relevant Account Holder, each
holder of a Note and each holder of a Coupon is a "Holder".

WHEREAS:

(A)  CIBA SPECIALTY CHEMICALS CORPORATION, CIBA SPECIALTY CHEMICALS PLC, CIBA
     SPEZIALITATENCHEMIE HOLDING DEUTSCHLAND GMBH (the "Issuers" and each an
     "Issuer") and the Guarantor have entered into an amended and restated
     Program Agreement (the "Program Agreement", which expression includes the
     same as it may be amended or supplemented from time to time) dated 30th
     March, 2001 with the Dealers named therein, which amends and restates the
     amended and restated program agreement entered into by, inter alia, Ciba
     Specialty Chemicals Corporation, Ciba Specialty Chemicals PLC and Ciba
     Spezialitatenchemie Holding Deutschland GmbH dated 16th June, 2000 (the
     "Principal Program Agreement"), under which each Issuer proposes from
     time to time to issue Euro Medium Term Notes (the "Notes", such
     expression to include each Definitive Note issued by an Issuer and each
     Global Note issued by an Issuer (where "Definitive Note" and "Global
     Note" have the meanings ascribed thereto in the Agency Agreement defined
     below) and to include any receipts issued in respect of Notes repayable
     in instalments);

(B)  each Issuer has executed a Deed of Covenant of even date (the "Deed of
     Covenant") relating to Global Notes issued by that Issuer pursuant to the
     Program Agreement;

(C)  the Issuers and the Guarantor have entered into an amended and restated
     agency agreement (the "Agency Agreement", which expression includes the
     same as it may be amended or supplemented from time to time) dated 30th
     March, 2001 with the Paying Agents named therein; and

(D)  this Deed of Guarantee amends and restates the amended and restated Deed
     of Guarantee made by the Guarantor dated 16th June, 2000, and does not
     affect any Notes issued pursuant to the Principal Program Agreement prior
     to the date hereof.

NOW THIS DEED WITNESSES as follows:

1.   Guarantee: The Guarantor irrevocably and unconditionally undertakes to
     secure by way of deed poll to each Holder the due and punctual payment as
     stipulated in an Issuer's Note or Coupon or under its Deed of Covenant,
     as the case may be. The Guarantor therefore undertakes to pay on first
     demand of such a Holder, irrespective of the validity and the legal
     effects of the above mentioned relationship in respect of a Note or
     Coupon or Deed of Covenant and waiving all rights of objection and
     defence arising therefrom any amount not paid by the relevant Issuer
     (including any premium or any other amounts of whatever nature or
     additional amounts) upon receipt of the written request for payment by
     such Holder and the confirmation in writing by the Agent that the
     relevant Issuer has not made such payments on the dates specified and in
     the amount called under the Guarantee. The Guarantor hereby expressly
     undertakes and secures that payments under this Guarantee will not be
     less than as stipulated in an Issuer's Note or Coupon. In implementation
     of this undertaking and in case Swiss withholding taxes are imposed in
     respect of payments made under this Guarantee, the


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     Guarantor undertakes, as a separate and independent obligation, to pay an
     increased amount on the relevant Note or Coupon so that the payment
     received by the Noteholder or Couponholder shall equal the amount
     actually stipulated in such Note or Coupon (assuming no such withholding
     applies).

2.   Guarantor's Obligations Continuing: The Guarantor's obligations under
     this Guarantee are and will remain in full force and effect by way of
     continuing security until no sum remains payable under any Note, any
     Coupon or the Deed of Covenant. Furthermore, these obligations of the
     Guarantor are additional to, and not instead of, any security or other
     guarantee or indemnity at any time existing in favour of a Holder,
     whether from the Guarantor or otherwise. The Guarantor irrevocably waives
     all notices and demands whatsoever, except as provided herein.

3.   Repayment to the Issuer: If any payment received by a Holder is, on the
     subsequent liquidation or insolvency of the relevant Issuer, avoided
     under any laws relating to liquidation or insolvency, such payment will
     not be considered as having discharged or diminished the liability of the
     Guarantor and this Guarantee will continue to apply as if such payment
     had at all times remained owing by the relevant Issuer.

4.   Status of Guarantee: The payment obligations of the Guarantor under this
     Guarantee constitute direct, unconditional and (subject to clause 5
     below) unsecured obligations of the Guarantor and (subject as aforesaid)
     rank and will rank pari passu with all other outstanding unsecured and
     unsubordinated indebtedness and monetary obligations of the Guarantor,
     present or future, including those in respect of deposits (other than
     obligations preferred by law).

5.   Negative Pledge of the Guarantor: So long as any of the Notes remains
     outstanding, but not later than the time when payment for the full amount
     of principal and interest in respect of all outstanding Notes has been
     duly provided for, the Guarantor will procure that no Indebtedness of the
     Guarantor which is represented by bonds, notes or other securities which
     in any such case are listed or capable of being listed on any recognised
     Stock Exchange will be secured upon any of the present or future assets
     or revenues of the Guarantor unless all amounts payable under this
     Guarantee are secured equally and rateably with such other security or
     such other security or guarantee is granted to the Notes and Coupons as
     shall have been approved by an Extraordinary Resolution of the
     Noteholders. Any reference to an obligation being guaranteed shall
     include a reference to an indemnity being given in respect of payment
     thereof.

     As used herein "Indebtedness" means all indebtedness for money borrowed
     that is created, assumed, incurred or guaranteed in any manner by the
     Guarantor or for which the Guarantor is otherwise responsible or liable.

6.   Tax Gross-up: All payments in respect of the Notes by the Guarantor shall
     be made without withholding or deduction for, or on account of, any
     present or future taxes, duties, assessments or governmental charges of
     whatever nature ("Taxes") imposed or levied by or on behalf of
     Switzerland, or any political sub-division of, or any authority in, or
     of, Switzerland having power to tax, unless the withholding or deduction
     of the Taxes is required by law. In that event, the Guarantor will pay
     such additional amounts as may be necessary in order that the net amounts
     received by the Noteholders and Couponholders after the withholding or
     deduction shall equal the respective amounts which would have been
     receivable in respect of the Notes or, as the case may be, Coupons in the
     absence of the withholding or deduction; except that no additional amount
     shall be payable in relation to any payment in respect of any Note or
     Coupon:


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     (i)  by or on behalf of a person liable to such tax, duty or charge in
          respect of such Note, Receipt or Coupon by reason of his having some
          connection with Switzerland other than the mere holding or ownership
          of such Note, Receipt or Coupon; and/or

     (ii) presented for payment to the relevant Issuer more than 30 days after
          the Relevant Date (as defined in Condition 7(f) of the Terms and
          Conditions of the relevant Notes) except to the extent that a holder
          would have been entitled to additional amounts on presenting the
          same for payment on the last day of the period of 30 days; and/or

     (iii) to, or to a third party on behalf of, a holder who would be able to
          avoid such withholding or deduction by making a declaration of
          non-residence or similar claim for exemption but fails to do so;
          and/or

     (iv) where such withholding or deduction is imposed on a payment to an
          individual and is required to be made pursuant to any European Union
          Directive on the taxation of savings implementing the conclusions of
          the ECOFIN Council meeting of November 26-27, 2000, or any law
          implementing or complying with, or introduced in order to conform
          to, such Directive; and/or

     (v)  presented for payment by or on behalf of a holder who would have
          been able to avoid such withholding or deduction by presenting the
          relevant Note or Coupon to another Paying Agent in a Member State of
          the EU.

7.   Power to execute: The Guarantor hereby warrants, represents and covenants
     with each Holder that it has all corporate power, and has taken all
     necessary corporate or other steps, to enable it to execute, deliver and
     perform this Guarantee, and that this Guarantee constitutes a legal,
     valid and binding obligation of the Guarantor, enforceable in accordance
     with its terms subject to applicable bankruptcy, reorganisation,
     insolvency, fraudulent transfer, moratorium and other similar laws
     affecting creditor's rights generally from time to time in effect, and to
     general principles of equity, regardless of whether considered in a
     proceeding in law or at equity.

8.   Deposit of Guarantee: This Guarantee shall take effect as a Deed Poll for
     the benefit of the Holders from time to time and for the time being. This
     Guarantee shall be deposited with and held by The Chase Manhattan Bank
     for the benefit of the Holders until all the obligations of the Guarantor
     hereunder have been discharged in full.

9.   Production of Guarantee: The Guarantor hereby acknowledges the right of
     every Holder to the production of, and the right of every Holder to
     obtain (upon payment of a reasonable charge) a copy of, this Guarantee,
     and further acknowledges and covenants that the obligations binding upon
     it contained herein are owed to, and shall be for the account of, each
     and every Holder, and that each Holder shall be entitled severally to
     enforce the said obligations against the Guarantor.

10.  Subrogation: Until all amounts which may be payable under the Notes, the
     Coupons and/or the Deed of Covenant have been irrevocably paid in full,
     the Guarantor shall not exercise any rights of subrogation in respect of
     any rights of any Holder or claim in competition with the Holders against
     the relevant Issuer.

11.  Governing Law and Jurisdiction: This Guarantee is governed by and shall
     be construed in accordance with English law. The Guarantor irrevocably
     agrees for the benefit of each Holder that the courts of England are to
     have jurisdiction to settle any disputes which may


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     arise out of or in connection with this Guarantee and that accordingly
     any suit, action or proceedings arising out of or in connection with this
     Guarantee (together referred to as "Proceedings") may be brought in the
     courts of England.

     The Guarantor irrevocably waives any objection which it may have now or
     hereafter to the laying of the venue of the Proceedings in the courts of
     England and irrevocably agrees that a final judgment in any Proceedings
     brought in the courts of England shall be conclusive and binding upon the
     Guarantor and may be enforced in the courts of any other jurisdiction.
     Nothing contained in this clause shall limit any right to take
     Proceedings against the Guarantor in any other court of competent
     jurisdiction, nor shall the taking of Proceedings in none or more
     jurisdictions preclude the taking of Proceedings in any other
     jurisdiction, whether concurrently or not.

     No rights are conferred on any person under the Contracts (Rights of
     Third Parties) Act 1999 to enforce any term of this Global Note, but this
     does not affect any right or remedy of any person which exists or is
     available apart from that Act.

     The Guarantor hereby appoints Ciba Specialty Chemicals PLC as its agent
     for service of process in England in respect of any Proceedings and
     undertakes that in the event of it ceasing so to act it will appoint
     another person as its agent for that purpose.

IN WITNESS whereof this Guarantee has been manually executed as a deed poll on
behalf of the Guarantor.

Executed as a deed             )
by CIBA SPECIALTY CHEMICALS    )
HOLDING INC.                   )   OLIVER STRUB      KIRK ERSTLING
acting by its attorneys        )

and in the presence of:        )


Witness's
Signature:  ..................................... A. STEINER

Name:       ..................................... ANITER STEINER

Address:    ..................................... c/o CIBA SPECIALTY CHEMICALS

            .....................................

Dated 30th March, 2001