Amendment No. 2 to Second Amended and Restated Investors' Rights Agreement by and among NuVasive, Inc. and Investors

EXHIBIT 4.3

NUVASIVE, INC.

AMENDMENT NO. 2 TO
SECOND AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT

        This Amendment No. 2 to Second Amended and Restated Investors' Rights Agreement (this "Amendment") is made as of February 5, 2004 by and among NuVasive, Inc., a Delaware corporation (the "Company"), the persons and entities listed on Schedule A hereto (each, an "Investor" and collectively, the "Investors"). Capitalized terms used herein which are not defined herein shall have the definition ascribed to them in the Second Amended and Restated Investors' Rights Agreement dated July 11, 2002 among the Company and the persons and entities listed therein (the "Agreement").

RECITALS

        A.    The Company and the Investors have previously entered into the Agreement and that certain Amendment No. 1 to the Agreement dated June 19, 2003 ("Amendment No. 1").

        B.    In consideration of the proposed underwritten initial public offering of common stock of the Company (the "Offering"), the Company and the Investors desire to amend certain provisions of the Agreement.

        C.    The undersigned parties are sufficient to effect an amendment to the Agreement pursuant to Section 3.7 thereof.

RECITALS

        NOW THEREFORE, for good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto agree as follows:

        1.    Section 2.5(i).    Section 2.5(i) is hereby amended and restated in its entirety to read as follows:

"(i) the sale of securities pursuant to a registration statement filed by the Company under the Act in connection with a firm commitment underwritten offering of its securities to the general public, at an offering price of at least $5.00 per share (as adjusted for any stock dividends, stock splits, combinations or other recapitalizations with respect to such shares) and $25,000,000 in the aggregate"

        2.    Effect of Amendment.    Except as expressly modified by this Amendment, the Agreement and Amendment No. 1 shall remain unmodified and in full force and effect.

        3.    Entire Agreement.    This Amendment together with the Agreement, Amendment No. 1 and all documents referred to herein and therein constitute the full and entire understanding and agreement between the parties with regard to the subjects hereof and thereof.

        4.    Governing Law.    This Amendment shall be governed by and construed under the laws of the State of California as applied to agreements among California residents entered into and performed entirely within California.

        5.    Counterparts.    This Amendment may be executed in two or more counterparts and the signatures delivered in facsimile, each of which shall be deemed an original, with the same effect as if the signatures were upon the same instrument and delivered in person.

        6.    Amendments and Waivers.    Any term of this Amendment may be amended or modified only upon the written consent of the Company and the persons and entities holding at least sixty six and two-thirds percent (66²/3%) of the Registrable Securities then outstanding. Any amendment or waiver effected in accordance with this paragraph shall be binding upon all the Investors, each transferee and the Company.

[SIGNATURE PAGES TO FOLLOW]

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

[SIGNATURE PAGE TO AMENDMENT NO. 2 TO
SECOND AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT]

        IN WITNESS WHEREOF, the parties have executed this Amendment as of the date first written above. The undersigned take this action with respect to all shares of the Company's capital stock owned by the undersigned.

SCHEDULE A

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EXHIBIT 4.3