[6-K] TANTECH HOLDINGS LTD Current Report (Foreign Issuer)

U.S. SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER

THE SECURITIES EXCHANGE ACT OF 1934

For the month of December 2025

Commission File Number: 001-36885

Tantech Holdings Ltd

(Registrant’s name)

No. 10 Cen Shan Road, Shuige Industrial Zone

Lishui City, Zhejiang Province 323000

+86-578-226-2305

(Address of principal executive offices)

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

Form 20-F ☒      Form 40-F ☐

Explanatory Note:

The Registrant is filing this Report on Form 6-K to provide its proxy statement for its 2025 annual shareholder meeting.

Exhibits No.		Description
99.1		Notice of Annual Meeting of Shareholders and Proxy Statement
99.2		Proxy Card

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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, thereunto duly authorized.

	Tantech Holdings Ltd
Date: December 11, 2025	By:	/s/ Zheyuan Liu
	Name:	Zheyuan Liu
	Title:	Chief Executive Officer

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FAQ

What is the purpose of Tantech Holdings Ltd's December 2025 Form 6-K (TANH)?

The Form 6-K from Tantech Holdings Ltd furnishes materials related to its annual meeting of shareholders, including a Notice of Annual Meeting and Proxy Statement and a Proxy Card as exhibits.

What exhibits are attached to this Tantech Holdings Ltd (TANH) SEC filing?

The filing lists two exhibits: Exhibit 99.1, the Notice of Annual Meeting of Shareholders and Proxy Statement, and Exhibit 99.2, the Proxy Card.

What type of issuer is Tantech Holdings Ltd (TANH) in this SEC report?

Tantech Holdings Ltd is identified as a foreign private issuer submitting a report under the Securities Exchange Act of 1934.

Where are the principal executive offices of Tantech Holdings Ltd (TANH) located?

The principal executive offices of Tantech Holdings Ltd are at No. 10 Cen Shan Road, Shuige Industrial Zone, Lishui City, Zhejiang Province 323000, with telephone +86-578-226-2305.

Who signed the December 2025 SEC report for Tantech Holdings Ltd (TANH)?

The report was signed on behalf of Tantech Holdings Ltd by Zheyuan Liu, who is identified as the Chief Executive Officer, dated December 11, 2025.

What shareholder materials does Tantech Holdings Ltd (TANH) provide through this SEC submission?

Through this submission, Tantech Holdings Ltd provides a Notice of Annual Meeting of Shareholders and Proxy Statement, and a Proxy Card, as Exhibits 99.1 and 99.2.