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Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
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X0202 SCHEDULE 13D/A 0000950123-08-002960 0000921669 XXXXXXXX LIVE 19 Common Stock, par value $0.01 per share 03/25/2026 false 0000727510 293904108 VISKASE HOLDINGS, INC. 333 East Butterfield Road Suite 400 Lombard IL 60148 Jesse Lynn, Esq. 305-442-4000 Icahn Capital LP, 16690 Collins Avenue Suite PH-1 Sunny Isles Beach FL 33160 Joshua Apfelroth 212-969-3000 Proskauer Rose LLP Eleven Times Square New York NY 10036 Louis Rambo 202-416-6800 Proskauer Rose LLP 1001 Pennsylvania Ave. NW, Suite 600 Washington DC 20004 0000921669 N CARL C ICAHN OO Y X1 0 13426451 0 13426451 13426451 N 93.7 IN 0001034563 N ICAHN ENTERPRISES HOLDINGS L.P. OO Y DE 0 13426451 0 13426451 13426451 N 93.7 PN 0001257324 N ICAHN ENTERPRISES G.P. INC. OO Y DE 0 13426451 0 13426451 13426451 N 93.7 CO Common Stock, par value $0.01 per share VISKASE HOLDINGS, INC. 333 East Butterfield Road Suite 400 Lombard IL 60148 This statement constitutes Amendment No. 19 to the Schedule 13D relating to the shares of Common Stock, par value $0.01 per share (the "Shares"), issued by Viskase Holdings, Inc. (formerly known as Enzon Pharmaceuticals, Inc.), a Delaware corporation (the "Issuer"), and amends the Schedule 13D relating to the Shares filed on March 14, 2008 (as previously amended, the "Original 13D"), on behalf of the Reporting Persons (as defined in Item 2 of Amendment No. 16 to the Schedule 13D). Capitalized terms used herein and not otherwise defined have the respective meanings ascribed thereto in the Original 13D. Item 4 of the Original 13D is hereby amended and supplemented as follows: On March 25, 2026, in connection with the closing of the previously announced Merger between the Issuer and Viskase Companies, Inc. ("Viskase") and pursuant to the terms of the IEH Support Agreement, the Reporting Persons exchanged 39,277 shares of Preferred Stock for 5,658,396 shares of the Issuer's Common Stock. On March 26, 2026 (the "Closing Date"), the Issuer completed the Merger with Viskase pursuant to the Merger Agreement. In connection with the Merger and pursuant to the Merger Agreement, the Reporting Persons received 7,407,489 shares of the Issuer in exchange for 150,810,078 shares of Viskase. Robert Flint, Colin Kwak, and Dustin DeMaria were appointed to the Issuer's board of directors in connection with the closing of the Merger. Mr. Flint is the Chief Accounting Officer of Icahn Enterprises L.P. Mr. Kwak is the head trader at Icahn Capital LP, an affiliate of the Reporting Persons. Mr. DeMaria is a Senior Analyst at Ichan Enterprises L.P., an affiliate of the Reporting Persons. Items (a)-(c) of the Original 13D are hereby amended and supplemented as follows: The information set forth in rows 11 and 13 of the cover pages hereto is incorporated herein by reference. The percentages set forth on the cover pages are based on 14,331,713 outstanding Shares as of March 26, 2026, as reported by the Issuer to the Reporting Persons. The information set forth in rows 7-10 of the cover pages hereto is incorporated herein by reference. The information set forth in Item 4 herein is incorporated herein by reference. Except for the transaction set forth in Item 4, none of the Reporting Persons effected any transaction in the Shares in the past 60 days. CARL C ICAHN /s/ Carl C. Icahn Carl C. Icahn 03/27/2026 ICAHN ENTERPRISES HOLDINGS L.P. /s/ Ted Papapostolou Ted Papapostolou, Chief Financial Officer 03/27/2026 ICAHN ENTERPRISES G.P. INC. /s/ Ted Papapostolou Ted Papapostolou, Chief Financial Officer 03/27/2026