Mustang Bio, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Notes Payable (Narrative) (Details)

v3.22.1

Notes Payable (Narrative) (Details)		3 Months Ended
Notes Payable (Narrative) (Details)	Mar. 04, 2022 USD ($) $ / shares shares	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Upfront fees		$ 2,634,000	$ 0
Amortization of debt discount		19,000	$ 0
Runway Debt Facility
Long-term debt facility	$ 75,000,000.0
Amount funded upon closing	30,000,000.0
Amount available under facility	45,000,000.0
Upfront fees	$ 400,000
Commitment fee percentage	1.00%
Security deposit	$ 75,000
Advisory and legal fees	$ 2,300,000
Warrants issued \| shares	748,036
Warrant exercise price (in dollars per share) \| $ / shares	$ 0.8021
Warrant term	10 years
Amortization of debt discount		$ 19,400
Final payment as a percentage of original principal	3.50%
Final Payment	$ 1,000,000.0
Runway Debt Facility \| Warrants [Member]
Fair value	$ 400,000
Runway Debt Facility \| Warrants [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Fair value of warrants assumptions	1.74
Runway Debt Facility \| Warrants [Member] \| Measurement Input, Price Volatility [Member]
Fair value of warrants assumptions	57.3
Runway Debt Facility \| Minimum
Variable interest rate floor (as a percent)	9.25%
Runway Debt Facility \| Base Rate
Variable interest rate floor (as a percent)	8.75%
Runway Debt Facility \| Three month LIBOR
Variable interest rate floor (as a percent)	0.50%

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