AMENDMENT NO. 1 TO RIGHTS AGREEMENT

Exhibit 4.3 – Amendment No. 1 to Rights Agreement

AMENDMENT NO. 1 TO RIGHTS AGREEMENT

This AMENDMENT NO. 1 TO RIGHTS AGREEMENT (this “Amendment”) is dated as of December 29, 2010, among O’Reilly Automotive, Inc., a Missouri corporation (the “Company”), O’Reilly Holdings, Inc., a Missouri corporation (“New O’Reilly”), and Computershare Trust Company, N.A., as successor rights agent to UMB Bank, N.A. (the “Rights Agent”). Capitalized terms used herein and not otherwise defined shall have the meaning ascribed to them in the Rights Agreement (as defined below).

W I T N E S S E T H:

WHEREAS, the Company and UMB Bank, N.A., a national banking association, previously entered into a Rights Agreement, dated as of May 7, 2002 (the “Rights Agreement”);

WHEREAS, the Company desires to reorganize itself by adopting a holding company structure pursuant to and in accordance with Section 351.448 of The General Corporation Law of the State of Missouri (the “Reorganization”);

WHEREAS, New O’Reilly is a newly formed, direct, wholly owned subsidiary of the Company organized for the purpose of implementing the Reorganization;

WHEREAS, each of the Company, New O’Reilly and O’Reilly MergerCo, Inc., a Missouri corporation (“MergerCo”), and a newly formed, direct, wholly owned subsidiary of New O’Reilly, are parties to that certain Agreement and Plan of Merger (the “Merger Agreement”), dated as of the date hereof;

WHEREAS, pursuant to the Merger Agreement, MergerCo will merge with and into the Company (the “Merger”), with the Company being the surviving corporation and becoming a direct, wholly owned subsidiary of New O’Reilly;

WHEREAS, as a result of the Merger, (i) each share of the Company’s common stock, par value $.01 per share (the “Company Common Stock”), issued and outstanding at the effective time of the Merger (the “Effective Time”), will be converted into a share of common stock, par value $.01 per share (the “New O’Reilly Common Stock”), of New O’Reilly, with the same designations, rights, powers, preferences, qualifications, limitations and restrictions as the Company Common Stock;

WHEREAS, at the Effective Time, the Company’s restated articles of incorporation will be amended by virtue of the Merger to, among other things, change the Company’s name to O’Reilly Automotive Stores, Inc., and New O’Reilly’s articles of incorporation will be amended by virtue of the Merger to change New O’Reilly’s name to O’Reilly Automotive, Inc.; and

WHEREAS, the parties hereto desire to amend the Rights Agreement pursuant to and in accordance with Section 27 thereof to provide for New O’Reilly to succeed to the rights and obligations of the Company thereunder.

NOW THEREFORE, the parties, intending to be legally bound, do hereby agree as follows:

“Section 2. Appointment of Rights Agent. The Company hereby appoints the Rights Agent to acts as agent for the Company in accordance with the terms and conditions hereof, and the Rights Agent hereby accepts such appointment. The Company may from time to time appoint such co-rights agents as it may deem necessary or desirable, upon ten (10) days’ prior written notice to the Rights Agent. The Rights Agent shall have no duty to supervise, and shall in no event be liable for, the acts or omissions of any such co-rights agents.”

“The Rights Agent shall be liable hereunder only for its own gross negligence, bad faith or willful misconduct.”

“In the event the transfer agency relationship in effect between the Company and the Rights Agent terminates, the Rights Agent will be deemed to have resigned automatically and be discharged from its duties under this Agreement as of the effective date of such termination, and the Company shall be responsible for sending any notice required, if applicable, pursuant to this Section 21 and Section 25 hereof.”

“Computershare Trust Company, N.A.

250 Royall Street

Canton, Massachusetts 02021

Attention: Client Services”

“Section 35. Force Majeure. Notwithstanding anything to the contrary contained herein, the Rights Agent shall not be liable for any delays or failures in performance resulting from acts beyond its reasonable control including, without limitation, acts of God, terrorist acts, shortage of supply, breakdowns or malfunctions, interruptions or malfunction of computer facilities, or loss of data due to power failures or mechanical difficulties with information storage or retrieval systems, labor difficulties, war, or civil unrest.”

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

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