Summary of financial instruments at fair value based on the fair value hierarchy or each class of instrument

The following tables summarize the Company’s financial instruments at fair value based on the fair value hierarchy for each class of instrument (in thousands):


	Fair Value Measurement
December 31, 2023	Level 1		Level 2		Level 3
Liabilities:
Warrant liability	$	—	$	—	$	(20	)
Mudrick convertible notes		—		—		(40,370	)
Super priority note payable		—		—		(18,568	)
	$	—	$	—	$	(58,958	)


	Fair Value Measurement
June 30, 2024	Level 1		Level 2		Level 3
Assets:
Money market account	$	2,544	$	—	$	—
Liabilities:
Warrant liability	$	—	$	—	$	(30	)
Mudrick convertible notes		—		—		(54,850	)
Super priority note payable		—		—		(50,130	)
	$	—	$	—	$	(105,010	)

Schedule of binomial lattice model for initial measurement of private placement warrants

The Company calculated the estimated fair value of the private warrants as of June 30, 2024 and December 31, 2023, respectively, using the following assumptions:


	June 30, 2024
Stock price	$	0.14
Exercise price	$	11.50
Risk-free interest rate		4.43	%
Time to expiration (years)		3.44
Expected volatility		101.64	%
Fair value per warrant	$	0.006


	December 31, 2023
Stock price	$	0.24
Exercise price	$	11.50
Risk-free interest rate		3.89	%
Time to expiration (years)		3.94
Expected volatility		77.15	%
Fair value per warrant	$	0.004

Schedule of changes in the level 3 convertible promissory notes and super priority note payable measured at fair value

The following table presents changes in the Level 3 convertible promissory notes and Super Priority Note Payable measured at fair value for the periods indicated (in thousands):


	June 30, 2024
	Mudrick Convertible Notes		Mudrick Super Priority Note Payable
Balance (beginning of period)	$	40,370	$	18,568
Additions		—		41,172
Fair value measurement adjustments		14,480		(9,610	)
Balance (end of period)	$	54,850	$	50,130