UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16

of the Securities Exchange Act of 1934

September 18, 2013

Commission File Number: 1-15174

Siemens Aktiengesellschaft

(Translation of registrant’s name into English)

Wittelsbacherplatz 2

80333 Munich

Federal Republic of Germany

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F x Form 40-F ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):

Yes ¨ No x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):

Yes ¨ No x

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes ¨ No x

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-

Investor Relations

Munich, September 18, 2013

Ad-hoc Announcement

according to § 15 WpHG (Securities Trading Act)

The Supervisory Board of Siemens AG appointed Ralf Thomas as CFO and nominated Jim Hagemann Snabe to be appointed member of the Supervisory Board

At its meeting today, the Siemens Supervisory Board appointed Ralf Thomas as the new CFO, previously responsible for this function in the Industry Sector.

Klaus Helmrich is taking over the post of Labor Director of Siemens AG in addition to his previous responsibility as Chief Technology Officer.

Brigitte Ederer, whose responsibilities on the Siemens Managing Board have included human resources, is resigning by mutual agreement from her position as of September 30, 2013.

The current Co-CEO of SAP, Jim Hagemann Snabe, is to be appointed member of the Supervisory Board by court order on application by the company as successor to Josef Ackermann, who is leaving the Siemens Supervisory Board at his own request on September 30, 2013. This was decided by the Siemens Supervisory Board at its meeting today.

The Supervisory Board of Siemens AG has also appointed Werner Wenning as Deputy Chairman and member of the Chairman’s Committee of the Supervisory Board.

Disclaimer

This document contains statements related to our future business and financial performance and future events or developments involving Siemens that may constitute forward-looking statements. These statements may be identified by words such as “expects,” “looks forward to,” “anticipates,” “intends,” “plans,” “believes,” “seeks,” “estimates,” “will,” “project” or words of similar meaning. We may also make forward-looking statements in other reports, in presentations, in material delivered to stockholders and in press releases. In addition, our representatives may from time to time make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Siemens’ management, and are, therefore, subject to certain risks and uncertainties. A variety of factors, many of which are beyond Siemens’ control, affect Siemens’ operations, performance, business strategy and results and could cause the actual results, performance or achievements of Siemens to be materially different from any future results, performance or achievements that may be expressed or implied by such forward-looking statements or anticipated on the basis of historical trends. These factors include in particular, but are not limited to, the matters described in Item 3: Key information—Risk factors of our most recent annual report on Form 20-F filed with the SEC, in the chapter “Risks” of our most recent annual report prepared in accordance with the German Commercial Code, and in the chapter “Report on risks and opportunities” of our most recent interim report.

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Siemens AG

CF IR

Investor Relations

D-80312 Munich

Mariel von Drathen

Wittelsbacherplatz 2

D-80333 Munich

Phone: +49-89 636 32474; Fax: -32830

E-Mail: investorrelations@siemens.com

Further information about risks and uncertainties affecting Siemens is included throughout our most recent annual and interim reports, as well as our most recent earnings release, which are available on the Siemens website, www.siemens.com, and throughout our most recent annual report on Form 20-F and in our other filings with the SEC, which are available on the Siemens website, www.siemens.com, and on the SEC’s website, www.sec.gov. Should one or more of these risks or uncertainties materialize, or should underlying assumptions prove incorrect, actual results, performance or achievements of Siemens may vary materially from those described in the relevant forward-looking statement as being expected, anticipated, intended, planned, believed, sought, estimated or projected. Siemens neither intends, nor assumes any obligation, to update or revise these forward-looking statements in light of developments which differ from those anticipated.

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Siemens AG

CF IR

Investor Relations

D-80312 Munich

Mariel von Drathen

Wittelsbacherplatz 2

D-80333 Munich

Phone: +49-89 636 32474; Fax: -32830

E-Mail: investorrelations@siemens.com

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, thereunto duly authorized.


	SIEMENS AKTIENGESELLSCHAFT

Date: September 18, 2013

	/S/ DR. JOCHEN SCHMITZ
	Name:	Dr. Jochen Schmitz
	Title:	Corporate Vice President and Controller

	/S/ DR. JUERGEN M. WAGNER
	Name:	Dr. Juergen M. Wagner
	Title:	Head of Financial Disclosure and Corporate Performance Controlling

SIEMENS AKTIENGESELLSCHAFT 6-K