Exhibit 5.2

November 18, 2015

AGL Capital Corporation

2215-B Renaissance Drive

Las Vegas, Nevada 89119

Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as special Nevada counsel to AGL Capital Corporation, a Nevada corporation (the “Company”), in connection with the offer and sale by the Company of its 3.875% Senior Notes due 2025, in the aggregate principal amount of $250,000,000.00 (the “Notes”) and the related guarantee thereof (the “Guarantee”) by AGL Resources Inc., a Georgia corporation (the “Guarantor”). The Notes will be issued pursuant to an indenture dated as of February 20, 2001, among the Company, as issuer, the Guarantor, as guarantor, and The Bank of New York Trust Mellon Company, N.A., (formerly known as The Bank of New York Trust Company) as successor in interest to The Bank of New York, as trustee (the “Indenture”). The offer and sale of the Notes and the Guarantee have been registered pursuant to a Registration Statement on Form S-3 (Registration Nos. 333-190280, 333-190280-01 and 333-190280-02) filed by the Company, the Guarantor and one of their affiliates (the “Registration Statement”). The Company and the Guarantor have entered into an Underwriting Agreement dated as of November 13, 2015, by and among the Company, the Guarantor, Mitsubishi UFJ Securities (USA) Inc., SunTrust Robinson Humphrey, Inc., and Wells Fargo Securities, LLC, for themselves and on behalf of the Underwriters listed on Schedule A thereto (the “Underwriting Agreement”), relating to the sale of the Notes and the Guarantee. Capitalized terms not defined herein shall have such meaning as set forth in the Underwriting Agreement.

In connection with the Opinions, we have examined copies of the following documents:

AGL Capital Corporation

November 18, 2015

Page 2

During the course of such examination and review, and in connection with furnishing the opinions set forth below, we have assumed the accuracy and completeness of all documents and records that we have reviewed, the genuineness of all signatures, the legal capacity of all natural persons, the authenticity of the documents submitted to us as originals and the conformity to authentic original documents of all documents submitted to us as certified, conformed or reproduced copies. We are familiar with the proceedings taken and proposed to be taken by the Guarantor and the Company in connection with the authorization and issuance of the Notes and the Guarantee, and, for the purposes of this opinion letter, we have assumed that any future, similar or other required proceedings will be timely completed in the manner presently contemplated.

AGL Capital Corporation

November 18, 2015

Page 3

Based upon the foregoing, and subject to the limitations, qualifications, exceptions and assumptions set forth herein, we are of the opinion that:

1. The Company is a corporation duly incorporated, validly existing and in good standing under the laws of the State of Nevada.

2. The Underwriting Agreement and the Notes have been authorized by all necessary corporate action on the part of the Company.

Our examination of matters of law in connection with the opinions expressed herein has been limited to, and accordingly our opinions expressed herein are limited to, the laws of the State of Nevada. We express no opinion with respect to the laws of any other jurisdiction.

This opinion is given as of the date hereof, and we assume no obligation to advise you after the date hereof of facts or circumstances that come to our attention or changes in law that occur that could affect the opinions contained herein.

This opinion letter is being furnished in connection with the offer and sale of the Notes and the Guarantee pursuant to the registration requirements of the Securities Act of 1933, as amended (the “Securities Act”). We hereby consent to the reliance upon this opinion of Troutman Sanders LLP, counsel to the Company and Guarantor, in connection with that firm’s opinion to the Company and Guarantor. We hereby consent to your filing this opinion as an exhibit to the Guarantor’s Current Report on Form 8-K, which is incorporated by reference in the Registration Statement, and to the reference to our firm contained under the caption “Validity of the Senior Notes” in the prospectus included therein. In giving this consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Securities and Exchange Commission promulgated thereunder.