# EDGAR Filing Document

**Accession Number:** 0001429260
**File Stem:** 0001415889-25-015470
**Filing Date:** 2025-6
**Character Count:** 8032
**Document Hash:** c7a2a7b777eff098caf685e5ca9fac88
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001415889-25-015470.hdr.sgml**: 20250603

**ACCESSION NUMBER**: 0001415889-25-015470

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20250529

**FILED AS OF DATE**: 20250603

**DATE AS OF CHANGE**: 20250603

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Fortress Biotech, Inc.
- **CENTRAL INDEX KEY:** 0001429260
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38128
- **FILM NUMBER:** 251021342

**BUSINESS ADDRESS:**
- **STREET 1:** 1111 KANE CONCOURSE
- **STREET 2:** SUITE 301
- **CITY:** BAY HARBOR ISLANDS
- **STATE:** FL
- **ZIP:** 33154
- **BUSINESS PHONE:** 781-652-4500

**MAIL ADDRESS:**
- **STREET 1:** 1111 KANE CONCOURSE
- **STREET 2:** SUITE 301
- **CITY:** BAY HARBOR ISLANDS
- **STATE:** FL
- **ZIP:** 33154

**FORMER NAME:**
- **FORMER CONFORMED NAME:** CORONADO BIOSCIENCES INC
- **DATE OF NAME CHANGE:** 20080310
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Checkpoint Therapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001651407
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 472568632
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 95 SAWYER ROAD
- **STREET 2:** SUITE 110
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02453
- **BUSINESS PHONE:** 781-652-4500

**MAIL ADDRESS:**
- **STREET 1:** 95 SAWYER ROAD
- **STREET 2:** SUITE 110
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02453

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[x] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Fortress Biotech, Inc.<br><sub>(Last) (First) (Middle)</sub><br>1111 KANE CONCOURSE<br>SUITE 301<br><sub>(Street)</sub><br>BAY HARBOR ISLANDS, FL 33154<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2025-05-29 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Checkpoint Therapeutics, Inc. [ CKPT ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| COMMON STOCK, PAR VALUE $0.0001 | 2025-05-29 |  | S |  | 100000 | D | 1.29<sup>(1)</sup> | 6122249 | D |  |
| COMMON STOCK, PAR VALUE $0.0001 | 2025-05-30 |  | D |  | 6122249 | D | 4.10<sup>(2)</sup> | 0 | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| CLASS A COMMON STOCK, PAR VALUE $0.0001 | $4.10 | 2025-05-30 |  | D |  |  | 700000 | <sup>(2)(3)</sup> | <sup>(2)(3)</sup> | Common Stock | 700000 | $0 | 0 | D |  |

---

### Footnotes:

(1) On July 15, 2015, pursuant to the Fortress Biotech, Inc. Long Term Incentive Plan, the Reporting Person issued warrants to purchase 500,000 shares of Issuer common stock (out of the Reporting Person's holdings in the Issuer) to each of Lindsay A. Rosenwald and Michael S. Weiss (collectively, the "Warrants"). Following a December 2022 reverse stock split by the Issuer, the Warrants became exercisable into 100,000 shares of Issuer common stock in the aggregate, with an exercise price of $1.29 per share. Dr. Rosenwald and Mr. Weiss exercised the Warrants on May 29, 2025.

(2) On March 9, 2025, the Issuer entered into an Agreement and Plan of Merger (the "Merger Agreement") by and among the Issuer, Sun Pharmaceutical Industries, Inc., a Delaware corporation ("Parent"), and Snoopy Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Parent ("Merger Sub").  On May 30, 2025 (the "Closing Date"), Merger Sub merged with and into the Issuer pursuant to the Merger Agreement, with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent (the "Merger"). As a result of the Merger, each issued and outstanding share of Common Stock and Class A Common Stock that was previously held by the Reporting Person was automatically canceled and ceased to exist and was converted into the right to receive: (i) $4.10 in cash, without interest, and (ii) one non-tradable contingent value right (a "CVR"), which represents the right to receive a contingent cash payment of up to $0.70 upon the achievement of a specified milestone.

(3) Each share of Class A Common Stock had no expiration date and was convertible at any time at the option of Reporting Person into one share of the Issuer's Common Stock.

**Signature:** /s/ Samuel Berry, Attorney-in-Fact  
**Date:** 2025-06-03

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**