FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

Exhibit 2.1

FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

This FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER (this “Amendment”), dated as of January 6, 2013 is entered into by and among Realty Income Corporation, a Maryland corporation (“Parent”), Tau Acquisition LLC, a Delaware limited liability company and a direct wholly owned subsidiary of Parent, and American Reality Capital Trust, Inc., a Maryland corporation (each, a “Party”, and collectively, the “Parties”). Capitalized terms used herein and not otherwise defined shall have the same meanings as set forth in the Agreement and Plan of Merger, dated as of September 6, 2012, by and among the Parties (the “Agreement”).

WHEREAS, Section 8.4 of the Agreement provides that amendments may be made to the Agreement by execution of an instrument in writing signed by each of the Parties; and

WHEREAS, the Parties wish to amend the Agreement in order to add a cash component to the Merger Consideration as set forth herein.

NOW, THEREFORE, in consideration of the premises and the mutual covenants, agreements and provisions herein contained, the receipt and sufficiency of which is hereby acknowledged, the Parties agree as follows:

1. Amendments to Agreement.

(a) Section 1.1(b) of the Agreement is amended by adding the following terms:

(b) The first sentence of Section 3.1(b) of the Agreement is deleted in its entirety and replaced with the following:

“Each share of Company Common Stock issued and outstanding immediately prior to the Effective Time (other than shares to be cancelled in accordance with Section 3.1(a)) shall automatically be converted into the right to receive (i) 0.2874 (the “Exchange Ratio”) validly issued, fully paid and non-assessable shares (the “Stock Consideration”) of common stock, par value $0.01 per share of Parent (the “Parent Common Stock”), and (ii) $0.35 in cash (the “Cash Consideration”), subject to adjustment as provided in Section 3.1(d) (collectively, the “Merger Consideration”).”

(c) The second sentence of Section 3.2(a) of the Agreement is deleted in its entirety and replaced with the following:

“On or before the Effective Time, Parent shall deposit, or cause to be deposited, with the Exchange Agent (i) cash in immediately available funds and certificates representing the shares of Parent Common Stock sufficient to pay the Merger Consideration and (ii) cash in immediately available funds in an amount sufficient to pay the Fractional Share Consideration and any dividends under Section 3.2(d) (such certificates representing shares of Parent Common Stock and cash amounts, together with any dividends or other distributions with respect thereto, the “Exchange Fund”), in each case, for the sole benefit of the holders of shares of Company Common Stock.”

(d) The first sentence of Section 3.2(c)(ii) of the Agreement is deleted in its entirety and replaced with the following:

“Upon surrender of a Certificate (or affidavit of loss in lieu thereof) to the Exchange Agent, together with a Letter of Transmittal duly completed and validly executed in accordance with the instructions thereto, and such other documents as may reasonably be required by the Exchange Agent, the holder of such Certificate shall be entitled to receive in exchange therefor the Stock Consideration for each share of Company Common Stock formerly represented by such Certificate pursuant to the provisions of this Article III plus a check or wire transfer representing the Cash Consideration for each share of Company Common Stock formerly represented by such Certificate pursuant to the provisions of this Article III, the amount of cash such holder is entitled to receive in lieu of fractional shares of Parent Common Stock that such holder has the right to receive pursuant to the provisions of Section 3.1(b) and any amounts that such holder has the right to receive in respect of dividends or other distributions on shares of Parent Common Stock in accordance with Section 3.2(d), to be mailed or delivered by wire transfer, within two (2) Business Days following the later to occur of (A) the Effective Time or (B) the Exchange Agent’s receipt of such Certificate (or affidavit of loss in lieu thereof), and the Certificate (or affidavit of loss in lieu thereof) so surrendered shall be forthwith cancelled.”

(e) The third sentence of Section 5.3(a) of the Agreement is deleted in its entirety and replaced with the following:

“All issued and outstanding shares of the capital stock of Parent are duly authorized, validly issued, fully paid and non-assessable, and all shares of Parent Common Stock to be issued in connection with the Merger, when so issued in accordance with the terms of this Agreement, will be duly authorized, validly issued, fully paid and non-assessable.”

(f) Section 5.22 of the Agreement is deleted in its entirety and replaced with the following:

“Sufficient Funds. Parent has available, and Parent will provide Merger Sub at the Effective Time, sufficient cash or lines of credit available to pay the Cash Consideration, the Fractional Share Consideration, any and all amounts required to be paid in connection with the consummation of the transactions contemplated by this Agreement, including the Merger, and any related fees and expenses.”

2. Full Force and Effect; Amendment. Except as expressly amended hereby, each term, provision and Exhibit of the Agreement (i) is hereby ratified and confirmed, (ii) is hereby incorporated herein and (iii) will and does remain in full force and effect. This Amendment may not be amended except by an instrument in writing signed by the Parties.

3. Interpretation. The Parties have participated jointly in the negotiation and drafting of this Amendment. Consequently, in the event an ambiguity or question of intent or interpretation arises, this Amendment shall be construed as if drafted jointly by the Parties, and no presumption or burden of proof shall arise favoring or disfavoring any Party by virtue of the authorship of any provision of this Amendment. When a reference is made in this Amendment to a Section, such reference shall be to a Section of this Amendment, unless otherwise indicated. The headings for this Amendment are for reference purposes only and shall not affect in any way the meaning or interpretation of this Amendment.

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4. Severability. If any term or other provision of this Amendment is invalid, illegal or incapable of being enforced under any present or future Law, or public policy, (a) such term or other provision shall be fully separable, (b) this Amendment shall be construed and enforced as if such invalid, illegal or unenforceable provision had never comprised a part hereof, and (c) all other conditions and provisions of this Amendment shall remain in full force and effect and shall not be affected by the illegal, invalid or unenforceable term or other provision or by its severance herefrom so long as the economic or legal substance of the transactions contemplated by this Amendment is not affected in any manner materially adverse to any Party. Upon such determination that any term or other provision is invalid, illegal or incapable of being enforced, the Parties shall negotiate in good faith to modify this Amendment so as to effect the original intent of the Parties as closely as possible in a mutually acceptable manner in order that transactions contemplated by this Amendment be consummated as originally contemplated to the fullest extent possible.

5. Counterparts. This Amendment may be executed in one or more counterparts, and by the different Parties in separate counterparts, each of which when executed shall be deemed to be an original but all of which taken together shall constitute one and the same agreement. Delivery of an executed counterpart of a signature page to this Amendment by facsimile transmission or by e-mail of a pdf attachment shall be effective as delivery of a manually executed counterpart of this Amendment.

6. Governing Law. This Amendment and all Actions (whether based on contract, tort or otherwise), directly or indirectly, arising out of or relating to this Amendment or the actions of any Party in the negotiation, administration, performance and enforcement thereof, shall be governed by, and construed in accordance with, the laws of the State of Maryland, without giving effect to any choice or conflict of Laws provision or rule (whether of the State of Maryland or any other jurisdiction) that would cause the application of the Laws of any jurisdiction other than the State of Maryland.

7. Consent to Jurisdiction.

(a) Each of the Parties hereby irrevocably submits to the exclusive jurisdiction of the courts of the State of Maryland and to the jurisdiction of the United States District Court for the State of Maryland, for the purpose of any Action (whether based on contract, tort or otherwise), directly or indirectly, arising out of or relating to this Amendment or the actions of the Parties in the negotiation, administration, performance and enforcement thereof, and each of the Parties hereby irrevocably agrees that all claims in respect to such Action may be heard and determined exclusively in any Maryland state or federal court.

(b) Each of the Parties (i) irrevocably consents to the service of the summons and complaint and any other process in any other Action relating to the transactions contemplated by this Amendment, on behalf of itself or its property, by personal delivery of copies of such process to such Party and nothing in this Section 7 shall affect the right of any Party to serve legal process in any other manner permitted by Law, (ii) consents to submit itself to the personal jurisdiction of any United States federal court located in the State of Maryland or any Maryland state court in the event any dispute arises out of this Amendment or the transactions contemplated by this Amendment, (iii) agrees that it will not attempt to deny or defeat such personal jurisdiction by motion or other request for leave from any such court and (iv) agrees that it will not bring any Action relating to this Amendment or the transactions contemplated by this Amendment in any court other than any United States federal court located in the State of Maryland or any Maryland state court. Each of the Parties agrees that a final judgment in any Action shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by Law.

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8. WAIVER OF JURY TRIAL. EACH OF THE PARTIES ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY ARISE OUT OF OR RELATING TO THIS AMENDMENT IS LIKELY TO INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND THEREFORE EACH SUCH PARTY HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT SUCH PARTY MAY HAVE TO A TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT OR OTHERWISE), DIRECTLY OR INDIRECTLY, ARISING OUT OF OR RELATING TO THIS AMENDMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY, OR THE ACTIONS OF THE PARTIES IN THE NEGOTIATION, ADMINISTRATION, PERFORMANCE AND ENFORCEMENT THEREOF. EACH OF THE PARTIES CERTIFIES AND ACKNOWLEDGES THAT (A) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, (B) EACH SUCH PARTY UNDERSTANDS AND HAS CONSIDERED THE IMPLICATIONS OF THIS WAIVER, (C) EACH SUCH PARTY MAKES THIS WAIVER VOLUNTARILY, AND (D) EACH SUCH PARTY HAS BEEN INDUCED TO ENTER INTO THIS AMENDMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 8.

[Signature Page Follows]

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IN WITNESS WHEREOF, the Parties have caused this Amendment to be duly executed and delivered as of the date first written above by their respective officers thereunto duly authorized.

[Signature Page to First Amendment to Agreement and Plan of Merger]

[Signature Page to First Amendment to Agreement and Plan of Merger]