Enzon Pharmaceuticals (ENZN) extends Section 382 rights plan expiration to March 2, 2026

Rhea-AI Filing Summary

Enzon Pharmaceuticals, Inc. has amended its Section 382 Rights Agreement again, entering into a Seventh Amendment on January 30, 2026. This amendment changes the Final Expiration Date of the rights from the close of business on January 31, 2026 to noon New York City time on March 2, 2026.

The company states that management believes setting the new March 2, 2026 expiration is in the best interests of the company and its stockholders. Aside from this new expiration timing, all other terms of the Rights Agreement and prior amendments remain unchanged.

8-K Event Classification

3 items: 1.01, 3.03, 9.01

3 items

Item 1.01 Entry into a Material Definitive Agreement Business

The company signed a significant contract such as a merger agreement, credit facility, or major partnership.

Item 3.03 Material Modification to Rights of Security Holders Securities

A change was made that materially affects the rights of existing shareholders (e.g., dividend rights, voting rights).

Item 9.01 Financial Statements and Exhibits Exhibits

Financial statements, pro forma financial information, and exhibit attachments filed with this report.

Understanding 8-K Material Events →

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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): January 30, 2026

ENZON PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Delaware (State or other jurisdiction
of incorporation) 001-36435 (Commission File Number) 22-2372868 (IRS Employer Identification No.)

20 Commerce Drive (Suite 135), Cranford, New Jersey (Address of principal executive offices) 07016 (Zip Code)

(732) 980-4500

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since 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:

Title of each class		Trading Symbol(s)		Name of each exchange on which registered
None		N/A		N/A

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 1.01 Entry into a Material Definitive Agreement.

On January 30, 2026, Enzon Pharmaceuticals, Inc. (the “Company”) entered into the Seventh Amendment to the Section 382 Rights Agreement (the “Seventh Amendment”), which amends the Section 382 Rights Agreement, dated as of August 14, 2020 (the “Rights Agreement”), by and between the Company and Continental Stock Transfer & Trust Company, as rights agent. Effective as of June 2, 2021, the Company amended the Rights Agreement (the “First Amendment”) to extend the Final Expiration Date (as defined in the Rights Agreement) of the rights issued pursuant to the Rights Agreement from the close of business on August 13, 2021 to the close of business on June 2, 2024. Effective as of May 16, 2024, the Company amended the Rights Agreement (the “Second Amendment”) to extend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on June 2, 2024 to the close of business on March 31, 2025. Effective as of March 31, 2025, the Company entered into the Third Amendment (the “Third Amendment”) to extend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on March 31, 2025 to the close of business on June 30, 2026. On August 13, 2025, the Company entered into the Fourth Amendment (the “Fourth Amendment”), to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on June 30, 2026 to the close of business on September 30, 2025. On September 30, 2025, the Company entered into the Fifth Amendment (the “Fifth Amendment”) to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on September 30, 2025 to the close of business on December 31, 2025. On December 23, 2025, the Company entered into the Sixth Amendment (the “Sixth Amendment”) to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on December 31, 2025 to the close of business on January 31, 2026.

On January 30, 2026, the Company entered into the Seventh Amendment (the “Seventh Amendment”) to amend the Final Expiration Date of the rights issued pursuant to the Rights Agreement from the close of business on January 31, 2026 to noon New York City time on March 2, 2026. Except for the adjustment to the Final Expiration Date, the Rights Agreement otherwise remains unmodified.

The Seventh Amendment has been adopted because the Company’s management believes that it is in the best interests of the Company and its stockholders to provide for a Final Expiration Date of noon New York City time on March 2, 2026, as established in the Seventh Amendment.

The foregoing description does not purport to be complete and is qualified in its entirety by reference to the complete text of (i) the Rights Agreement, which was filed with the U.S. Securities and Exchange Commission (the “SEC”) as Exhibit 4.1 to the Company’s Registration Statement on Form 8-A filed with the SEC on August 14, 2020, (ii) the First Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on June 8, 2021, (iii) the Second Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on May 22, 2024, (iv) the Third Amendment, which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K filed on April 1, 2025, (v) the Fourth Amendment, which was filed with the SEC as Exhibit 4.1 to the Quarterly Report on Form 10-Q filed on August 14, 2025, (vi) the Fifth Amendment, a copy of which was filed with the SEC as Exhibit 4.1 to the Current Report on Form 8-K on September 30, 2025, (vi) the Sixth Amendment, a copy of which is attached as Exhibit 4.1 hereto to the Current Report on Form 8-K on December 23, 2025, and (vii) the Seventh Amendment, a copy of which is attached as Exhibit 4.1 hereto and incorporated herein by reference. The Rights Agreement, the First Amendment, the Second Amendment, the Third Amendment, the Fourth Amendment, the Fifth Amendment, Sixth Amendment, and Seventh Amendment are incorporated herein by reference.

Item 3.03 Material Modification to Rights of Security Holders.

The information set forth in Item 1.01 of this Current Report on Form 8-K is incorporated by reference into this Item 3.03.

Item 9.01 Financial Statements and Exhibits. 

(d) Exhibits.

Exhibit		Description
4.1		Seventh Amendment to the Section 382 Rights Agreement, dated as of January 30, 2026, by and between Enzon Pharmaceuticals, Inc. and Continental Stock Transfer & Trust Company.
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

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.

	ENZON PHARMACEUTICALS, INC.
	(Registrant)
Date: January 30, 2026
	By:	/s/ Richard L. Feinstein
	Name:	Richard L. Feinstein
	Title:	Chief Executive Officer, Chief Financial Officer and Secretary

FAQ

What change did Enzon Pharmaceuticals (ENZN) make to its Section 382 Rights Agreement?

Enzon Pharmaceuticals extended the Final Expiration Date of the rights under its Section 382 Rights Agreement. The Seventh Amendment moves the expiration from the close of business on January 31, 2026 to noon New York City time on March 2, 2026, with no other terms modified.

When does Enzon Pharmaceuticals' Section 382 rights plan now expire after the latest amendment?

The rights under Enzon Pharmaceuticals’ Section 382 Rights Agreement now expire at noon New York City time on March 2, 2026. Previously, the Final Expiration Date was the close of business on January 31, 2026, and earlier amendments set various prior expiration dates.

Did Enzon Pharmaceuticals change any terms of the Section 382 Rights Agreement besides the expiration date?

No, only the Final Expiration Date was adjusted in the Seventh Amendment. The company states that except for this new expiration of noon New York City time on March 2, 2026, all other provisions of the Rights Agreement and its prior amendments remain unmodified.

Why did Enzon Pharmaceuticals’ management adopt the Seventh Amendment to the Rights Agreement?

Management adopted the Seventh Amendment because it believes the new Final Expiration Date is in the best interests of the company and its stockholders. The amendment sets the rights to expire at noon New York City time on March 2, 2026, extending protection for a limited period.

How has Enzon Pharmaceuticals adjusted the Final Expiration Date of its rights plan over time?

Enzon has repeatedly amended the Rights Agreement to adjust its Final Expiration Date, moving it through various dates including August 13, 2021, June 2, 2024, March 31, 2025, September 30, 2025, December 31, 2025, January 31, 2026, and now March 2, 2026.

Where can investors find the full text of Enzon Pharmaceuticals’ Seventh Amendment to the Rights Agreement?

Investors can review the complete Seventh Amendment as Exhibit 4.1 to the company’s current report. The filing also incorporates by reference the original Section 382 Rights Agreement and all prior amendments, each previously filed as exhibits with the U.S. Securities and Exchange Commission.