ENZN · Viskase Holdings, Inc.

Received in exchange for 150,810,078 shares of Viskase Companies, Inc. in connection with the Merger.

This Form 4 is being filed by, and on behalf of, Mr. Carl C. Icahn, Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings") and Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP" and, collectively with Mr. Icahn and Icahn Enterprises Holdings, the "Reporting Persons"). Shares held directly by American Entertainment Properties Corp ("AEP").

AEPC Holdings LLC owns 100% of the equity of AEP. Icahn Enterprises Holdings owns a 100% interest in AEPC Holdings LLC. Icahn Enterprises L.P. owns a 99% limited partner interest in Icahn Enterprises Holdings. Carl C. Icahn is the indirect holder of approximately 87% of the issued and outstanding depositary units representing limited partnership interests in Icahn Enterprises L.P. Icahn Enterprises GP is the general partner of and owns a 1% general partner interest in each of Icahn Enterprises Holdings and Icahn Enterprises L.P. Icahn Enterprises GP is 100% owned by Beckton Corp ("Beckton"). Beckton is 100% owned by Mr. Icahn.

Each of AEP, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of the Issuer's shares of common stock except to the extent of his or its pecuniary interest therein, if any.

Disposed of in exchange for 5,658,396 shares of common stock of the Issuer in connection with the merger of the Issuer and Viskase Companies, Inc. (the "Merger"). Following the closing of the Merger on March 26, 2026, the combined company was renamed "Viskase Holdings, Inc."

Reflects the Issuer's 1-for-100 reverse stock split effected on March 25, 2026.

This Form 4 is being filed by, and on behalf of, Mr. Carl C. Icahn, Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings") and Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP" and, collectively with Mr. Icahn and Icahn Enterprises Holdings, the "Reporting Persons"). Shares held directly by American Entertainment Properties Corp ("AEP").

AEPC Holdings LLC owns 100% of the equity of AEP. Icahn Enterprises Holdings owns a 100% interest in AEPC Holdings LLC. Icahn Enterprises L.P. owns a 99% limited partner interest in Icahn Enterprises Holdings. Carl C. Icahn is the indirect holder of approximately 87% of the issued and outstanding depositary units representing limited partnership interests in Icahn Enterprises L.P. Icahn Enterprises GP is the general partner of and owns a 1% general partner interest in each of Icahn Enterprises Holdings and Icahn Enterprises L.P. Icahn Enterprises GP is 100% owned by Beckton Corp ("Beckton"). Beckton is 100% owned by Mr. Icahn.

Each of AEP, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of the Issuer's shares of common stock except to the extent of his or its pecuniary interest therein, if any.

Disposed of in exchange for 5,658,396 shares of common stock of the Issuer in connection with the merger of the Issuer and Viskase Companies, Inc. (the "Merger"). Following the closing of the Merger on March 26, 2026, the combined company was renamed "Viskase Holdings, Inc."

This Form 4 is being filed by, and on behalf of, Mr. Carl C. Icahn, Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings") and Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP" and, collectively with Mr. Icahn and Icahn Enterprises Holdings, the "Reporting Persons"). Shares held directly by American Entertainment Properties Corp ("AEP").

AEPC Holdings LLC owns 100% of the equity of AEP. Icahn Enterprises Holdings owns a 100% interest in AEPC Holdings LLC. Icahn Enterprises L.P. owns a 99% limited partner interest in Icahn Enterprises Holdings. Carl C. Icahn is the indirect holder of approximately 87% of the issued and outstanding depositary units representing limited partnership interests in Icahn Enterprises L.P. Icahn Enterprises GP is the general partner of and owns a 1% general partner interest in each of Icahn Enterprises Holdings and Icahn Enterprises L.P. Icahn Enterprises GP is 100% owned by Beckton Corp ("Beckton"). Beckton is 100% owned by Mr. Icahn.

Each of AEP, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of the Issuer's shares of common stock except to the extent of his or its pecuniary interest therein, if any.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis") (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions and the reporting persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commision, upon request, full information regarding the number of shares purchased at each separate price.

Represents Shares owned directly by the Foundation. Mr. Couchman is the sole trustee of the Foundation. By virtue of this relationship, Mr. Couchman may be deemed to beneficially own the Shares owned directly by the Foundation, however he has no pecuniary interest in such Shares.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis") (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions and the reporting persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commision, upon request, full information regarding the number of shares purchased at each separate price.

Represents Shares owned directly by Xstelos. Mr. Couchman is the controlling shareholder and Chief Executive Officer of Xstelos. By virtue of these relationships, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Xstelos. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

Represents the weighted average purchase price of multiple transactions, with shares purchased at prices ranging from $0.1502 to $0.1511 per share. The reporting person hereby undertakes to provide, upon request by the U.S. Securities and Exchange Commission staff, the issuer or a stockholder of the issuer, full information regarding the number of shares purchased at each separate price.

Represents the weighted average purchase price of multiple transactions, with shares purchased at prices ranging from $0.1526 to $0.155 per share. The reporting person hereby undertakes to provide, upon request by the U.S. Securities and Exchange Commission staff, the issuer or a stockholder of the issuer, full information regarding the number of shares purchased at each separate price.

Icahn Partners LP ("Icahn Partners") directly beneficially owns 21,132,725 shares of Common Stock, $0.01 par value per share ("Common Stock"), and 22,975 shares of Series C?Non-Convertible Redeemable?Preferred Stock, $0.01 par value per share ("Preferred Stock"), and Icahn Partners Master Fund LP ("Icahn Master") directly beneficially owns 14,923,911 shares of Common Stock and 16,302 shares of Preferred Stock.

On October 9, 2020, the subscription rights distributed by the Issuer in connection with its rights offering (the "Rights Offering") expired. The Reporting Persons acquired an aggregate of 39,277 units, at a price per unit of $1,090, for an aggregate purchase price of $42,811,930, constituting (x) the Reporting Persons' pro-rata share of the units issued in the Rights Offering (5,971 units) and (y) all units that remained unsubscribed for by other holders at the expiration of the Rights Offering (33,306 units). Each unit acquired by the Reporting Persons consisted of 750 shares of Common Stock and one share of Preferred Stock, resulting in the acquisition by the Reporting Persons of an aggregate of 29,457,750 shares of Common Stock and 39,277 shares of Preferred Stock.

Beckton Corp. ("Beckton") is the sole stockholder of Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP"), which is the general partner of Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings"). Icahn Enterprises Holdings is the sole member of IPH GP LLC ("IPH"), which is the general partner of Icahn Capital LP ("Icahn Capital"). Icahn Capital is the general partner of each of Icahn Onshore LP ("Icahn Onshore") and Icahn Offshore LP ("Icahn Offshore"). Icahn Onshore is the general partner of Icahn Partners. Icahn Offshore is the general partner of Icahn Master.

Beckton is 100 percent owned by Carl C. Icahn. As such, Mr. Icahn is in a position indirectly to determine the investment and voting decisions made by each of Icahn Partners and Icahn Master.

Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Partners owns. Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Master owns. Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

On October 9, 2020, the subscription rights distributed by the Issuer in connection with its rights offering (the "Rights Offering") expired. The Reporting Persons acquired an aggregate of 39,277 units, at a price per unit of $1,090, for an aggregate purchase price of $42,811,930, constituting (x) the Reporting Persons' pro-rata share of the units issued in the Rights Offering (5,971 units) and (y) all units that remained unsubscribed for by other holders at the expiration of the Rights Offering (33,306 units). Each unit acquired by the Reporting Persons consisted of 750 shares of Common Stock and one share of Preferred Stock, resulting in the acquisition by the Reporting Persons of an aggregate of 29,457,750 shares of Common Stock and 39,277 shares of Preferred Stock.

Icahn Partners LP ("Icahn Partners") directly beneficially owns 21,132,725 shares of Common Stock, $0.01 par value per share ("Common Stock"), and 22,975 shares of Series C?Non-Convertible Redeemable?Preferred Stock, $0.01 par value per share ("Preferred Stock"), and Icahn Partners Master Fund LP ("Icahn Master") directly beneficially owns 14,923,911 shares of Common Stock and 16,302 shares of Preferred Stock.

Beckton Corp. ("Beckton") is the sole stockholder of Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP"), which is the general partner of Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings"). Icahn Enterprises Holdings is the sole member of IPH GP LLC ("IPH"), which is the general partner of Icahn Capital LP ("Icahn Capital"). Icahn Capital is the general partner of each of Icahn Onshore LP ("Icahn Onshore") and Icahn Offshore LP ("Icahn Offshore"). Icahn Onshore is the general partner of Icahn Partners. Icahn Offshore is the general partner of Icahn Master.

Beckton is 100 percent owned by Carl C. Icahn. As such, Mr. Icahn is in a position indirectly to determine the investment and voting decisions made by each of Icahn Partners and Icahn Master.

Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Partners owns. Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Master owns. Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

Icahn Partners LP ("Icahn Partners") directly beneficially owns 21,132,725 shares of Common Stock, $0.01 par value per share ("Common Stock"), and 22,975 shares of Series C?Non-Convertible Redeemable?Preferred Stock, $0.01 par value per share ("Preferred Stock"), and Icahn Partners Master Fund LP ("Icahn Master") directly beneficially owns 14,923,911 shares of Common Stock and 16,302 shares of Preferred Stock.

On October 9, 2020, the subscription rights distributed by the Issuer in connection with its rights offering (the "Rights Offering") expired. The Reporting Persons acquired an aggregate of 39,277 units, at a price per unit of $1,090, for an aggregate purchase price of $42,811,930, constituting (x) the Reporting Persons' pro-rata share of the units issued in the Rights Offering (5,971 units) and (y) all units that remained unsubscribed for by other holders at the expiration of the Rights Offering (33,306 units). Each unit acquired by the Reporting Persons consisted of 750 shares of Common Stock and one share of Preferred Stock, resulting in the acquisition by the Reporting Persons of an aggregate of 29,457,750 shares of Common Stock and 39,277 shares of Preferred Stock.

Beckton Corp. ("Beckton") is the sole stockholder of Icahn Enterprises G.P. Inc. ("Icahn Enterprises GP"), which is the general partner of Icahn Enterprises Holdings L.P. ("Icahn Enterprises Holdings"). Icahn Enterprises Holdings is the sole member of IPH GP LLC ("IPH"), which is the general partner of Icahn Capital LP ("Icahn Capital"). Icahn Capital is the general partner of each of Icahn Onshore LP ("Icahn Onshore") and Icahn Offshore LP ("Icahn Offshore"). Icahn Onshore is the general partner of Icahn Partners. Icahn Offshore is the general partner of Icahn Master.

Beckton is 100 percent owned by Carl C. Icahn. As such, Mr. Icahn is in a position indirectly to determine the investment and voting decisions made by each of Icahn Partners and Icahn Master.

Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Partners owns. Each of Icahn Onshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn may be deemed to indirectly beneficially own (as that term is defined in Rule 13d-3 under the Act) the shares of Common Stock and Preferred Stock which Icahn Master owns. Each of Icahn Offshore, Icahn Capital, IPH, Icahn Enterprises Holdings, Icahn Enterprises GP, Beckton and Mr. Icahn disclaims beneficial ownership of such shares except to the extent of their pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis"), Brian Harper, Harper Asset Management, LLC ("HAM"), and Michael Pearce, (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents shares owned directly by HAM. Mr. Harper is the President of HAM. By virtue of this relationship, Mr. Harper may be deemed to beneficially own the Shares owned directly by HAM. Mr. Harper expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis"), Brian Harper, Harper Asset Management, LLC ("HAM"), and Michael Pearce, (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents shares owned directly by HAM. Mr. Harper is the President of HAM. By virtue of this relationship, Mr. Harper may be deemed to beneficially own the Shares owned directly by HAM. Mr. Harper expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis"), Brian Harper, Harper Asset Management, LLC ("HAM"), and Michael Pearce, (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents Shares owned directly by Xstelos. Mr. Couchman is the controlling shareholder and Chief Executive Officer of Xstelos. By virtue of these relationships, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Xstelos. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis" and, together with Mr. Couchman, the Foundation and Xstelos, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents Shares owned directly by Myrexis. Mr. Couchman is Chief Executive Officer of Myrexis. By virtue of this relationship, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Myrexis. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis" and, together with Mr. Couchman, the Foundation and Xstelos, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents Shares owned directly by Myrexis. Mr. Couchman is Chief Executive Officer of Myrexis. By virtue of this relationship, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Myrexis. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis" and, together with Mr. Couchman, the Foundation and Xstelos, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents Shares owned directly by Myrexis. Mr. Couchman is Chief Executive Officer of Myrexis. By virtue of this relationship, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Myrexis. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.

This Form 4 is filed jointly by Jonathan Couchman ("Mr. Couchman"), Couchman Family Fund (the "Foundation"), Xstelos Corp. ("Xstelos") and Myrexis, Inc. ("Myrexis" and, together with Mr. Couchman, the Foundation and Xstelos, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Issuer's outstanding shares of Common Stock (the "Shares"). Each of the Reporting Persons expressly disclaims beneficial ownership of the Shares reported herein except to the extent of his or its pecuniary interest therein, and this report shall not be deemed to be an admission that any Reporting Person is the beneficial owner of such Shares for purposes of Section 16 or for any other purpose.

Represents Shares owned directly by Xstelos. Mr. Couchman is the controlling shareholder and Chief Executive Officer of Xstelos. By virtue of these relationships, Mr. Couchman may be deemed to beneficially own the Shares owned directly by Xstelos. Mr. Couchman expressly disclaims beneficial ownership of such Shares except to the extent of his pecuniary interest therein.