Form 8-K

8-K — SOUTHERN CO

Accession: 0000092122-26-000040

Filed: 2026-05-15

Period: 2026-05-13

CIK: 0000092122

SIC: 4911 (ELECTRIC SERVICES)

Item: Submission of Matters to a Vote of Security Holders

Item: Financial Statements and Exhibits

Documents

8-K — so-20260513.htm (Primary)

EX-3.1 (ex31socertificateofamendme.htm)

EX-3.2 (ex32sorestatedcertificateo.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: so-20260513.htm · Sequence: 1

so-20260513

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) May 13, 2026

Commission

File Number Registrant,

State of Incorporation,

Address and Telephone Number I.R.S. Employer

Identification No.

1-3526 The Southern Company 58-0690070

(A Delaware Corporation)

30 Ivan Allen Jr. Boulevard, N.W.

Atlanta, Georgia 30308

(404) 506-5000

The name and address of the registrant have not changed since the last report.

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Registrant Title of each class Trading

Symbol(s) Name of each exchange

on which registered

The Southern Company Common Stock, par value $5 per share SO New York Stock Exchange

The Southern Company Series 2017B 5.25% Junior Subordinated Notes due 2077 SOJC New York Stock Exchange

The Southern Company Series 2020A 4.95% Junior Subordinated Notes due 2080 SOJD New York Stock Exchange

The Southern Company

Series 2020C 4.20% Junior Subordinated Notes due 2060

SOJE New York Stock Exchange

The Southern Company Series 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081 SO 81 New York Stock Exchange

The Southern Company Series 2025A 6.50% Junior Subordinated Notes due 2085 SOJF New York Stock Exchange

The Southern Company 2025 Series A Corporate Units SOMN New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 5.07. Submission of Matters to a Vote of Security Holders.

The Southern Company (the “Company”) held its Annual Meeting of Stockholders on

May 13, 2026. Stockholders voted as follows on the ten matters presented for a vote:

1. The nominees for election to the Board of Directors were elected based on the following votes:

Nominees Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

Janaki Akella 784,876,449 98.68 % 10,432,453 2,053,270 179,338,232

Shantella E. Cooper 783,342,955 98.49 % 11,966,881 2,052,336 179,338,232

Anthony F. Earley, Jr. 778,970,288 97.94 % 16,310,213 2,081,671 179,338,232

James O. Etheredge 787,103,009 98.97 % 8,171,485 2,087,678 179,338,232

David J. Grain 771,268,167 96.98 % 24,003,646 2,090,359 179,338,232

John D. Johns 782,392,634 98.38 % 12,882,396 2,087,142 179,338,232

David E. Meador 780,239,348 98.10 % 15,074,948 2,047,876 179,338,232

William G. Smith, Jr. 772,562,017 97.14 % 22,714,125 2,086,030 179,338,232

Kristine L. Svinicki 779,969,354 98.06 % 15,380,351 2,012,467 179,338,232

Lizanne Thomas 774,256,082 97.34 % 21,142,031 1,964,059 179,338,232

John M. Turner, Jr. 787,367,826 99.00 % 7,923,303 2,071,043 179,338,232

Christopher C. Womack 773,084,318 97.20 % 22,205,419 2,072,435 179,338,232

2. The proposal to approve, on an advisory basis, the Company’s named executive officers’ compensation was approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

754,894,258 95.24 % 37,651,570 4,816,344 179,338,232

3. The proposal to ratify the appointment of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for 2026 was approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

947,424,572 97.24 % 26,799,479 2,476,353 N/A

4. The proposal to approve an amendment to the Company’s Restated Certificate of Incorporation to authorize additional common stock was approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

946,532,072 97.39 % 25,346,091 4,822,241 N/A

5. The proposal to approve an amendment to the Company’s Restated Certificate of Incorporation to authorize the issuance of preferred stock was approved based upon the following votes:

Votes For % Outstanding For Votes Against Abstentions Broker

Non-Votes

733,634,497 65.07 % 60,516,566 3,211,109 179,338,232

6. The proposal to approve an amendment to the Company’s Restated Certificate of Incorporation to provide for officer exculpation was approved based upon the following votes:

Votes For % Outstanding For Votes Against Abstentions Broker

Non-Votes

686,673,476 60.91 % 106,098,507 4,590,189 179,338,232

7. The proposal to approve miscellaneous amendments to the Company’s Restated Certificate of Incorporation to modernize, clarify and conform the Company’s Restated Certificate of Incorporation was approved based upon the following votes:

Votes For % Outstanding For Votes Against Abstentions Broker

Non-Votes

788,336,975 69.93 % 5,357,089 3,668,108 179,338,232

8. The stockholder proposal regarding an independent board chairman was not approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

103,219,771 13.06 % 686,754,673 7,387,728 179,338,232

9. The stockholder proposal regarding a report on data center costs was not approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

76,742,427 9.74 % 710,841,526 9,778,219 179,338,232

10. The stockholder proposal regarding a report on climate due diligence was not approved based upon the following votes:

Votes For % Votes Cast For Votes Against Abstentions Broker

Non-Votes

9,987,213 1.26 % 777,636,402 9,738,557 179,338,232

Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits.

3.1

Certificate of Amendment of Restated Certificate of Incorporation of the Company, effective May 13, 2026.

3.2

Restated Certificate of Incorporation of the Company, dated May 13, 2026.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: May 15, 2026

THE SOUTHERN COMPANY

/s/Melissa K. Caen

Melissa K. Caen

Assistant Secretary

EX-3.1

Filename: ex31socertificateofamendme.htm · Sequence: 2

Document

Exhibit 3.1

CERTIFICATE OF AMENDMENT

RESTATED CERTIFICATE OF INCORPORATION

THE SOUTHERN COMPANY

(Pursuant to Section 242 of the General Corporation Law of the State of Delaware)

The Southern Company, a Delaware corporation duly organized and existing under the General Corporation Law of the State of Delaware (the “Corporation”), does hereby certify that:

1. Article Third of the Restated Certificate of Incorporation of the Corporation, as amended (the “Charter”) is hereby amended in its entirety to read as follows:

“THIRD: The purpose of the corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware.”

2. Article Fourth of the Charter is hereby amended in its entirety to read as follows:

“FOURTH: The total number of shares of stock which the corporation shall have authority to issue is 2,550,000,000 shares, consisting of 2,500,000,000 shares of common stock with a par value of $0.01 each (the “Common Stock”) and 50,000,000 shares of preferred stock with a par value of $0.01 each (the “Preferred Stock.”).

The Board of Directors is hereby expressly authorized, by resolution or resolutions thereof, to provide, out of the unissued shares of Preferred Stock, for series of Preferred Stock and, with respect to each such series, to fix the number of shares constituting such series and the designation of such series, the powers (including voting powers (if any)) of the shares of such series, and the preferences and relative, participating, optional or other special rights, if any, and any qualifications, limitations or restrictions thereof, of the shares of such series. The powers, preferences and relative, participating, optional and other special rights of each series of Preferred Stock, and the qualifications, limitations or restrictions thereof, if any, may differ from those of any and all other series at any time outstanding.

Notwithstanding the foregoing and except as otherwise required by the Delaware General Corporation Law, no holder of Common Stock, as such, shall be entitled to vote on any amendment of this Certificate of Incorporation that exclusively alters, amends or changes the powers, preferences, rights or other terms of one or more outstanding series of Preferred Stock if the holders of such affected series are entitled, either separately or together with the holders of one or more

other series of Preferred Stock, to vote on the applicable amendment pursuant to this Certificate of Incorporation or pursuant to the Delaware General Corporation Law.”

3. Article Fifth of the Charter is hereby amended in its entirety to read as follows:

“FIFTH: Unless and except to the extent that the By-Laws of the corporation shall so require, the election of directors of the corporation need not be by written ballot.”

4. The Charter is hereby amended by deleting Article Sixth thereof in its entirety.

5. The Charter is hereby amended by deleting Article Seventh thereof in its entirety.

6. The Charter is hereby amended by deleting Article Eighth thereof in its entirety.

7. The last sentence of Section (1) of Article Ninth (which per paragraph 16 below will be renumbered as Article Sixth) of the Charter is hereby amended in its entirety to read as follows:

“Any director may be removed at any time with or without cause upon the affirmative vote of the holders of a majority in voting power of the stock of the corporation at that time entitled to vote at an election of directors.”

8. The Charter is hereby amended by deleting Section (2) of Article Ninth (which per paragraph 16 below will be renumbered as Article Sixth) thereof in its entirety.

9. The Charter is hereby amended by deleting Section (6) of Article Ninth (which per paragraph 16 below will be renumbered as Article Sixth) thereof in its entirety.

10. The Charter is hereby amended by deleting Section (7) of Article Ninth (which per paragraph 16 below will be renumbered as Article Sixth) thereof in its entirety.

11. The Charter is hereby amended by deleting Section (8) of Article Ninth (which per paragraph 16 below will be renumbered as Article Sixth) thereof in its entirety.

12. Section (10) (which per paragraph 16 below will be renumbered as section (6)) of Article Ninth of the Charter (which per paragraph 16 below will be renumbered as Article Sixth) is hereby amended in its entirety to read as follows:

“(10) The Board of Directors, in addition to the powers and authority expressly conferred upon it hereinbefore and by statute and by the By-Laws, is hereby empowered to exercise all such powers as may be exercised by the corporation;

subject, nevertheless, to the provisions of the statutes of the State of Delaware and of the Certificate of Incorporation.”

13. Section (11) (which per paragraph 16 below will be renumbered as section (7)) of Article Ninth of the Charter (which per paragraph 16 below will be renumbered as Article Sixth) is hereby amended in its entirety to read as follows (including renumbering and conforming of applicable cross-references):

“(7) A director or officer shall not be personally liable for monetary damages to the corporation or its stockholders for breach of fiduciary duty as a director or officer, as applicable, except (a) for directors and officers, for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (b) for directors and officers, for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) for directors, under section 174 of the General Corporation Law of the State of Delaware or any successor provision, (d) for directors and officers, for any transaction from which the director or officer derived an improper personal benefit or (e) for officers, in any action by or in the right of the corporation. If the General Corporation Law of the State of Delaware is hereafter amended to permit further elimination or limitation of the personal liability of directors or officers, then the liability of a director or officer of the corporation shall be eliminated or limited to the fullest extent permitted by the General Corporation Law of the State of Delaware as so amended. Any amendment, modification or repeal of this section shall not adversely affect any right or protection of a director or officer of the corporation hereunder in respect of any act or omission occurring prior to the time of such amendment, modification or repeal.”

14. The Charter is hereby amended by deleting Article Tenth thereof in its entirety.

15. Article Eleventh of the Charter (which per paragraph 16 below will be renumbered as Article Seventh) is hereby amended in its entirety to read as follows:

“The corporation reserves the right to increase or decrease its authorized capital stock, or any class or series thereof, or to reclassify the same, and to amend, alter, change or repeal any provision contained in the Certificate of Incorporation or in any amendment thereto, in the manner now or hereafter prescribed by law, and all rights conferred upon stockholders in said Certificate of Incorporation or any amendment thereto are granted subject to this reservation; provided, however, that the corporation shall not, unless authorized by the affirmative vote in favor thereof of the holders of at least a majority of the issued and outstanding common stock of the corporation given at any annual meeting of stockholders or at any special meeting called for that purpose, reclassify the common stock or change the issued shares of common stock into the same or a greater or less number of shares of common stock either with or without par value or reduce the par value of the common stock.”

16. The Charter, as amended as set forth above, is hereby amended by (i) renumbering Article Ninth, Article Eleventh and Article Twelfth as Article Sixth, Article Seventh and Article Eighth, respectively, and (ii) renumbering sections (3), (4), (5), (9), (10) and (11) of Article Ninth (which, pursuant to clause (i) is being renumbered as Article Sixth) as sections (2), (3), (4), (5), (6) and (7), respectively, and, in the case of both clauses (i) and (ii), making any conforming changes to cross references.

17. The foregoing amendments to the Charter were duly adopted in accordance with the provisions of Section 242 of the General Corporation Law of the State of Delaware.

[Signature Page Follows]

IN WITNESS WHEREOF, the Corporation has caused this Certificate to be executed by its duly authorized officer on this 13th day of May, 2026.

The Southern Company

/s/ Christopher C. Womack

Christopher C. Womack

Chairman, President and Chief Executive Officer

EX-3.2

Filename: ex32sorestatedcertificateo.htm · Sequence: 3

Document

Exhibit 3.2

RESTATED

CERTIFICATE OF INCORPORATION

THE SOUTHERN COMPANY

The Southern Company, a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “Delaware General Corporation Law”), does hereby certify that:

I. The present name of the corporation is The Southern Company. The corporation was incorporated under the name “Southeastern Power Holding Corp.” by the filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware (“Delaware Secretary of State”) on November 9, 1945. A Certificate of Amendment was filed with the Delaware Secretary of State on January 21, 1946, changing the name of the corporation to The Southern Company.

II. This Restated Certificate of Incorporation only restates and integrates and does not further amend the provisions of the Certificate of Incorporation of this corporation as heretofore amended or supplemented and there is no discrepancy between those provisions and the provisions of this Restated Certificate of Incorporation. This Restated Certificate of Incorporation has been duly adopted by the Board of Directors of the corporation in accordance with Section 245 of the Delaware General Corporation Law. The text of the Certificate of Incorporation is hereby restated and integrated to read in its entirety as follows:

FIRST: The name of the corporation is

THE SOUTHERN COMPANY

SECOND: The name of the county and the city, town or place within the county in which its principal office or place of business is to be located in the State of Delaware, and the street and number of such principal office or place of business is No. 251 Little Falls Drive, in the City of Wilmington, County of New Castle 19808. The name of its resident agent is Corporation Service Company and the address by street and number of said resident agent is No. 251 Little Falls Drive, Wilmington, Delaware 19808.

THIRD: The purpose of the corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware.

FOURTH: The total number of shares of stock which the corporation shall have authority to issue is 2,550,000,000 shares, consisting of 2,500,000,000 shares of common stock with a par value of $0.01 each (the “Common Stock”) and 50,000,000 shares of preferred stock with a par value of $0.01 each (the “Preferred Stock.”).

FIFTH: Unless and except to the extent that the By-Laws of the corporation shall so require, the election of directors of the corporation need not be by written ballot.

SIXTH: The following additional provisions are inserted for the management of the business and for the conduct of the affairs of the corporation and for the creation, definition, limitation and regulation of the powers of the corporation, the directors and the stockholders:

(1) The number of directors of the corporation which shall constitute the whole Board shall be such as from time to time shall be fixed by, or in the manner provided in, the By-Laws, and such number may be altered from time to time in the manner provided in such By-Laws, or by amendment thereof, adopted in the manner provided therein, but such number shall in no case be less than three. Vacancies caused by an increase in the number of directors or otherwise may be filled by the Board of Directors in the manner provided in the By-Laws. Directors need not be stockholders. Any director may be removed at any time with or without cause upon the affirmative vote of the holders of a majority in voting power of the stock of the corporation at that time entitled to vote at an election of directors.

(2) The Board of Directors shall also have power without the assent or vote of the stockholders to fix the times for the declaration and payment of dividends and to make and

determine the use and disposition of any surplus or net profits over and above the capital of the corporation.

(3) The Board of Directors shall also have power to make, alter, amend and repeal the By-Laws of the corporation, subject only to such limitations as the By-Laws of the corporation may from time to time impose.

(4) The Board of Directors shall also have power to sell, lease or exchange all or substantially all of the property and assets of the corporation, including its good will and corporate franchises, upon such terms and conditions and for such consideration, which may be in whole or in part shares of stock in, and/or other securities of, any other corporation or corporations, as the Board of Directors shall deem expedient and for the best interests of the corporation, when and as authorized by the affirmative vote in favor thereof of the holders of at least a majority of the issued and outstanding capital stock of the corporation having voting powers given at any annual meeting of stockholders or at any special meeting called for that purpose.

(5) The corporation shall be entitled to treat the person in whose name any share, right or option is registered as the owner thereof, for all purposes, and shall not be bound to recognize any equitable or other claim to or interest in such share, right or option on the part of any other person, whether or not the corporation shall have notice thereof, save as may be expressly provided otherwise by the laws of the State of Delaware.

(6) The Board of Directors, in addition to the powers and authority expressly conferred upon it hereinbefore and by statute and by the By-Laws, is hereby empowered to exercise all such powers as may be exercised by the corporation; subject, nevertheless, to the provisions of the statutes of the State of Delaware and of the Certificate of Incorporation.

(7) A director or officer shall not be personally liable for monetary damages to the corporation or its stockholders for breach of fiduciary duty as a director or officer, as applicable, except (a) for directors and officers, for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (b) for directors and officers, for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) for directors, under section 174 of the General Corporation Law of the State of Delaware or any successor provision, (d) for directors and officers, for any transaction from which the director or officer derived an improper personal benefit or (e) for officers, in any action by or in the right of the corporation. If the General Corporation Law of the State of Delaware is hereafter amended to permit further elimination or limitation of the personal liability of directors or officers, then the liability of a director or officer of the corporation shall be eliminated or limited to the fullest extent permitted by the General Corporation Law of the State of Delaware as so amended. Any amendment, modification or repeal of this section shall not adversely affect any right or protection of a director or officer of the corporation hereunder in respect of any act or omission occurring prior to the time of such amendment, modification or repeal.

SEVENTH: The corporation reserves the right to increase or decrease its authorized capital stock, or any class or series thereof, or to reclassify the same, and to amend, alter, change or repeal any provision contained in the Certificate of Incorporation or in any amendment thereto, in the manner now or hereafter prescribed by law, and all rights conferred upon stockholders in said Certificate of Incorporation or any amendment thereto are granted subject to this reservation; provided, however, that the corporation shall not, unless authorized by the affirmative vote in favor thereof of the holders of at least a majority of the issued and outstanding common stock of the corporation given at any annual meeting of stockholders or at

any special meeting called for that purpose, reclassify the common stock or change the issued shares of common stock into the same or a greater or less number of shares of common stock either with or without par value or reduce the par value of the common stock.

EIGHTH: No stockholder shall be entitled as a matter of right to subscribe for, purchase or receive any shares of the stock or any rights or options of the corporation which it may issue or sell, whether out of the number of shares authorized by this Certificate of Incorporation or by amendment thereof or out of the shares of the stock of the corporation acquired by it after the issuance thereof, nor shall any stockholder be entitled as a matter of right to purchase or subscribe for or receive any bonds, debentures or other obligations which the corporation may issue or sell that shall be convertible into or exchangeable for stock or to which shall be attached or appertain any warrant or warrants or other instrument or instruments that shall confer upon the holder or owner of such obligation the right to subscribe for or purchase from the corporation any shares of its capital stock, but all such additional issues of stock, rights, options, or of bonds, debentures or other obligations convertible into or exchangeable for stock or to which warrants shall be attached or appertain or which shall confer upon the holder the right to subscribe for or purchase any shares of stock may be issued and disposed of by the Board of Directors to such persons and upon such terms as in their absolute discretion they may deem advisable, subject only to such limitations as may be imposed in the Certificate of Incorporation or in any amendment thereto.

[Signature Page Follows]

IN WITNESS WHEREOF, The Southern Company has caused this Restated Certificate of Incorporation to be executed by its duly authorized officer on this 13th day of May, 2026.

The Southern Company

/s/ Christopher C. Womack

Christopher C. Womack

Chairman, President and Chief Executive Officer

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- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Exchange Act

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-Section 12

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Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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No definition available.

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Two-character EDGAR code representing the state or country of incorporation.

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No definition available.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

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-Subsection b-2

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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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-Publisher SEC

-Name Exchange Act

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Local phone number for entity.

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No definition available.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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- Definition

Title of a 12(b) registered security.

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-Section 12

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Name of the Exchange on which a security is registered.

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-Number 240

-Section 12

-Subsection d1-1

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Trading symbol of an instrument as listed on an exchange.

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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-Name Securities Act

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-Section 425

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