13D Filings
Enzon Pharmaceuticals, Inc.
ENZN
Amendment
Ownership

48.60%

Total Shares

36,056,636

Issuer CIK

727510

CUSIP

293904108

Event Date

Jun 19, 2025

Accepted

Jun 23, 2025, 08:19 AM

Reporting Persons (3)
Joint Filing

This is a joint filing. The reported shares may overlap between reporting persons and should not be summed.

NameType% of ClassAggregateSole VotingShared Voting
CARL C ICAHN
Individual
48.60%36,056,636036,056,636
ICAHN ENTERPRISES HOLDINGS L.P.
Partnership
48.60%36,056,636036,056,636
ICAHN ENTERPRISES G.P. INC.
CO
48.60%36,056,636036,056,636
Disclosure Items (5)

Security Title

Common Stock, par value $0.01 per share

Issuer Name

Enzon Pharmaceuticals, Inc.

Issuer Address

20 Commerce Drive, Suite 135, Cranford, NJ, 07016

Filing Persons

Items 2(a)-(c) of the Original 13D are hereby amended and restated as follows: The persons filing this statement are Icahn Enterprises Holdings L.P., a Delaware limited partnership ("Icahn Enterprises Holdings"), Icahn Enterprises G.P. Inc., a Delaware corporation ("Icahn Enterprises GP"), and Carl C. Icahn, a citizen of the United States of America (collectievely, the "Reporting Persons").

Business Address

The principal business address of each of Icahn Enterprises Holdings and Icahn Enterprises GP is 16690 Collins Avenue, PH-1, Sunny Isles Beach, FL 33160. The principal business address of Mr. Icahn is c/o Icahn Associates Holding LLC, 16690 Collins Avenue, PH-1, Sunny Isles Beach, FL 33160.

Principal Occupation

Icahn Enterprises Holdings is primarily engaged in the business of holding direct or indirect interests in various operating businesses. Icahn Enterprises GP is primarily engaged in the business of serving as the general partner of each of Icahn Enterprises L.P. and Icahn Enterprises Holdings. Carl C. Icahn's present principal occupation or employment is serving as (i) Chief Executive Officer of Icahn Capital LP, a wholly owned subsidiary of Icahn Enterprises L.P., through which Mr. Icahn manages various private investment funds, (ii) Chairman of the Board of Icahn Enterprises GP, the general partner of Icahn Enterprises L.P., a Nasdaq listed diversified holding company engaged in a variety of businesses, including investment, energy, automotive, food packaging, real estate, home fashion and pharma, and (iii) Chairman of the Board and a director of Starfire Holding Corporation ("Starfire"), a holding company engaged in the business of investing in and/or holding securities of various entities, and as Chairman of the Board and a director of various of Starfire's subsidiaries.

Item 4 of the Original 13D is hereby amended and supplemented as follows: Agreement and Plan of Merger of the Issuer and Viskase On June 20, 2025, the Issuer, EPSC Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of the Issuer ("Merger Sub"), and Viskase Companies, Inc., a Delaware corporation ("Viskase"), entered into an Agreement and Plan of Merger (the "Merger Agreement"). Subsidiaries of Icahn Enterprises Holdings currently own approximately 81% of the outstanding shares of Viskase. Upon the terms and subject to the satisfaction or waiver of the conditions described in the Merger Agreement, Merger Sub will be merged with and into Viskase, with Viskase surviving the Merger as a wholly owned subsidiary of the Issuer (the "Merger"). The Merger is intended to qualify as a tax-free reorganization for U.S. federal income tax purposes. Following the consummation of the Merger (the "Closing"), it is anticipated that the combined company will operate under the name "Viskase Holdings, Inc." and will trade on the "OTCQX" tier of the OTC market of the OTC Markets Group, Inc. The Merger Agreement has been unanimously recommended by a Special Committee of the independent directors of the Issuer (the "Enzon Special Committee") and a Special Committee of the independent directors of Viskase and, acting upon such recommendations, has been unanimously approved by the Boards of Directors of each of the Issuer and Viskase. The Merger Agreement provides, among other things, that on the terms and subject to the conditions set forth therein, at the effective time of the Merger: (i) each share of common stock, par value $0.01 per share, of Viskase (the "Viskase Common Stock") issued and outstanding immediately prior to the Merger (other than shares held by holders that properly exercise dissenters rights, shares held in treasury, and shares held by the Issuer) will be automatically converted into the right to receive the number of Shares equal to the exchange ratio as calculated under the Merger Agreement (the "Merger Consideration"); (ii) all shares of Viskase Common Stock converted into the right to receive the Merger Consideration will automatically be cancelled and will cease to exist as of the effective time of the Merger; and (iii) each share of the Issuer's Series C Non-Convertible Redeemable Preferred Stock, par value $0.01 per share (the "Series C Preferred Stock"), held by affiliates of the Reporting Persons will be exchanged for Shares at a discount to its liquidation value based upon the 20-day volume weighted average price ("VWAP") of the Shares prior to execution of the Merger Agreement; and (iv) pursuant to the terms of an exchange offer to be commenced by the Issuer, each share of Series C Preferred Stock held by non-affiliates of the Reporting Persons will have the right to be exchanged for Shares at its liquidation value based upon the 20-day VWAP of the Shares prior to execution of the Merger Agreement. Under the exchange ratio formula in the Merger Agreement and assuming that the Series C Preferred Stock is exchanged for Shares in full, upon closing of the Merger, (x) the holders of Shares immediately prior to the closing of the Merger are expected to own approximately 2.06% of the combined company's common stock, (y) the holders of Series C Preferred Stock, including the Reporting Persons, are expected to own approximately 13.84% of the combined company's common stock and (z) Viskase stockholders are expected to own approximately 84.1% of the combined company's common stock, subject to certain adjustments based upon the number of shares of Series C Preferred Stock exchanged for Shares by non-affiliates of the Reporting Persons and the amount of cash held by the Issuer at the effective time of the Merger, and depending on the liquidation value of the Series C Preferred Stock at the date of closing of the Merger. Upon the Closing, it is anticipated that the Reporting Persons will beneficially own approximately 91% of the combined company. The Chief Executive Officer of the combined company will be Timothy P. Feast, who is currently the Chief Executive Officer of Viskase. The Board of Directors of the combined company will be selected by the Board of Directors of Viskase and include Jordan Bleznick, a current member of the Issuer's Board of Directors and former employee of Icahn Enterprises L.P. The Closing is subject to the satisfaction or waiver of certain customary closing conditions. The foregoing description does not purport to be complete and is qualified in its entirety by reference to the complete text of the Merger Agreement, a copy of which is attached as Exhibit 1 hereto and incorporated herein by reference. IEH Support Agreement In connection with the execution and delivery of the Merger Agreement, Icahn Enterprises Holdings and certain of its affiliates entered into a support agreement (the "IEH Support Agreement") with the Issuer and Viskase, pursuant to which Icahn Enterprises Holdings and certain of its affiliates agreed (among other things) to, subject to the terms and conditions set forth therein, (i) deliver or cause the delivery of written consents with respect to all of the issued and outstanding shares of Enzon Common Stock held by Icahn Enterprises Holdings and its affiliates approving the Merger and the amendment to the Issuer's certificate of incorporation, and (ii) immediately prior to the Closing, exchange each issued and outstanding share of the Series C Preferred Stock held by Icahn Enterprises Holdings and its affiliates for Shares at a discount to its liquidation value based upon the 20-day VWAP of the Shares prior to execution of the Merger Agreement. The foregoing description does not purport to be complete and is qualified in its entirety by reference to the complete text of the IEH Support Agreement, a copy of which is attached as Exhibit 2 hereto and incorporated herein by reference.

Item 6 of the Original 13D is hereby amended and supplemented as follows: The disclosure set forth in Item 4 of this Schedule 13D is incorporated herein by reference.

The exhibit list in Item 7 of the Original 13D is hereby amended and supplemented by adding the following exhibit: 1. Merger Agreement, dated June 20, 2025 (incorporated by reference to Exhibit 2.1 to the Current Report on Form 8-K filed by Enzon Pharmaceuticals, Inc. on June 23, 2025) 2. Support Agreement, dated June 20, 2025 (incorporated by reference to Exhibit 10.1 to the Current Report on Form 8-K filed by Enzon Pharmaceuticals, Inc. on June 23, 2025)

Enzon Pharmaceuticals, Inc. — Schedule 13D | 13D Filings