AMENDMENT TO AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

Exhibit 4.3

AMENDMENT TO
AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

     THIS AMENDMENT TO AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT (this “Amendment”) is made as of February 2, 2007, with respect to that certain Amended and Restated Investor Rights Agreement (the “Agreement”) dated as of October 9, 2001, by and among Mellanox Technologies, Ltd., an Israeli company (the “Company”), and the other parties thereto.

     WHEREAS, the Company has filed a registration statement on Form S-1 in connection with the proposed initial public offering of its ordinary shares (the “IPO”);

     WHEREAS, Section 14 of the Agreement provides that, except as otherwise provided therein, any provision of the Agreement may be amended or the observance thereof may be waived (either generally or in a particular instance and either retroactively or prospectively) only with the written consent of the Company and the Holders of a majority of the Registrable Securities then outstanding, and that any amendment or waiver effected in accordance with Section 14 of the Agreement shall be binding upon each Purchaser, Holder of Registrable Securities at the time outstanding, each future holder of any such securities, the Founders and the Company; and

     WHEREAS, in connection with the proposed IPO, the Company and the undersigned Holders, representing the Holders of a majority of the Registrable Securities currently outstanding, desire to amend the Agreement as set forth herein.

     NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company and the Holders agree as follows:

     1. Definitions. Capitalized terms used herein but not separately defined herein shall have the meanings ascribed to them in the Agreement.

     2. Amendments.

(a) Section 5.10 of the Agreement is hereby amended to read in its entirety as follows:

     “5.10 Termination of Registration Rights. The rights granted pursuant to Sections 5.1, 5.2 and 5.3 of this Agreement shall terminate as to any Holder upon the earlier of (i) the date five years after the effective date of Company’s initial public offering of its Ordinary Shares and (ii) the date such Holder is able to immediately sell all shares of Registrable Securities held or entitled to be held upon conversion by such Holder under Rule 144 during any 90-day period without regard to Rule 144(k).”

(b) Section 12 of the Agreement is hereby amended to read in its entirety as follows:

     “12. Transfer of Rights.

            (a) The rights granted under Section 5 of this Agreement may be assigned to any transferee or assignee, other than a competitor or potential competitor of the Company (as determined in good faith by the Company’s Board of Directors) in connection with any transfer or assignment of Registrable Securities by the Holder; and

            (b) notwithstanding the foregoing, the rights granted under Section 5 of this Agreement may be assigned to any wholly-owned subsidiary of a Holder in connection with any transfer or assignment of Registrable Securities by such Holder;

     provided that: (i) each such transfer is otherwise effected in accordance with applicable securities laws and the terms of this Agreement; (ii) prior written notice is given to the Company; (iii) such transferee or assignee agrees to be bound by the provisions of this Agreement; and (iv) such transferee acquires at least 50,000 shares of Registrable Securities.”

(c) A new Section 20 is hereby added to the Agreement, which shall read in its entirety as follows:

          “20. Termination of Certain Covenants. Notwithstanding anything to the contrary contained in the Agreement, Sections 6 (Financial Information Rights), 7 (Observers), 8 (Use of Proceeds), 10 (Right of First Refusal), 11 (Confidential Information and Invention Assignment Agreements), 13 (Agreement to Vote) and 19 (Grant of Proxy) of the Agreement shall terminate and be of no further force or effect upon the consummation of the Company’s initial public offering of its Ordinary Shares.”

     3. Merger. Except as expressly amended above, the Agreement shall remain in full force and effect and the provisions thereof are hereby incorporated by reference (including, without limitation, Section 18).

(Signature pages follow)

             IN WITNESS WHEREOF, the parties have executed this Amendment as of the date first above written.

SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED INVESTOR
RIGHTS AGREEMENT OF MELLANOX TECHNOLOGIES, LTD.

SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED INVESTOR
RIGHTS AGREEMENT OF MELLANOX TECHNOLOGIES, LTD.

SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED INVESTOR
RIGHTS AGREEMENT OF MELLANOX TECHNOLOGIES, LTD.

SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED INVESTOR
RIGHTS AGREEMENT OF MELLANOX TECHNOLOGIES, LTD.