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SCHEDULE Filed 2026-01-05 Event 2026-01-02 SEC 0001104659-26-000690 →

Fortress Biotech, Inc. MUSTANG BIO, INC. MBIO

Stake: 8.00% Shares: 537,243 CUSIP: 62818Q302 Class: Common Stock, $0.0001 Par Value

Item 4 — Purpose of Transaction

The Reporting Person is party to that certain Second Amended and Restated Founders Agreement with the Issuer (as amended, the "Founders Agreement"), in connection with the Issuer's formation. Pursuant to the Issuer's Amended and Restated Certificate of Incorporation (as amended, the "Charter"), the Issuer issues annually to the Reporting Person shares of common stock equal to two and one-half percent (2.5%) of the fully-diluted outstanding equity of the Issuer, as measured as of the date of such issuance (the "Annual Equity Grant"). The foregoing description of the Charter and Founders Agreement are qualified in its entirety by reference to the full text of the Charter and Founders Agreement which are incorporated herein by reference as Exhibits 7.01, 7.02, and 7.04.

Cross-References

Insider Activity (last 365d)
0 transactions
0 buys · 0 sales · 0 awards/exercises
Issuer Cluster
3 13D/G filings on this issuer
2 other filings besides this one
Filer Track Record
9 filings by this filer
8 other filings in the data moat
Short Interest · settle 2026-03-31
DTC 3.31
125,433 shares short · +48.1% vs prior

Other 13D/G Filings on MUSTANG BIO, INC.

FiledFormFilerStakeShares
2025-04-02 SCHEDULE Fortress Biotech, Inc. 7.90% 199,191 view →
2025-01-03 SCHEDULE Fortress Biotech, Inc. 12.40% 6,569,450 view →

Other Filings by Fortress Biotech, Inc.

FiledFormIssuerStakeShares
2026-01-06 SCHEDULE AVENUE THERAPEUTICS, INC. ATXI 13.40% 439,955 view →
2025-04-02 SCHEDULE AVENUE THERAPEUTICS, INC. ATXI 10.30% 328,746 view →
2025-04-02 SCHEDULE MUSTANG BIO, INC. MBIO 7.90% 199,191 view →
2025-01-03 SCHEDULE AVENUE THERAPEUTICS, INC. ATXI 13.80% 295,022 view →
2025-01-03 SCHEDULE MUSTANG BIO, INC. MBIO 12.40% 6,569,450 view →
2025-01-03 SCHEDULE Checkpoint Therapeutics, Inc. 13.50% 6,903,749 view →
2024-10-01 SC Checkpoint Therapeutics, Inc. view →
2023-07-06 SC Checkpoint Therapeutics, Inc. view →

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