Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2024

Schedule of components and classification of stock-based compensation expense

The components and classification of stock-based compensation expense, excluding the Company’s matching contributions to the Plug Power Inc. 401(k) Savings & Retirement Plan and quarterly Board compensation, were as follows (in thousands):

	Three months ended				Nine months ended
	September 30, 2024		September 30, 2023		September 30, 2024		September 30, 2023
Cost of sales	$	1,459	$	3,115	$	5,544	$	8,231
Research and development		2,028		2,935		6,621		6,982
Selling, general and administrative		17,784		36,392		42,224		104,278
	$	21,271	$	42,442	$	54,389	$	119,491

Nonvested Restricted Stock Shares Activity

The following table reflects the restricted stock and restricted stock unit activity for the nine months ended September 30, 2024 (in thousands except share amounts):

		Weighted		Aggregate
		Average Grant Date		Intrinsic
	Shares	Fair Value		Value
Unvested restricted stock as of December 31, 2023	6,732,884	$	15.66	$	30,298
Granted	1,075,557		2.81		—
Vested	(1,784,759)		15.81		—
Forfeited	(1,199,185)		17.22		—
Unvested restricted stock as of September 30, 2024	4,824,497	$	12.35	$	10,903

Service Stock Options Awards

Schedule of Share-based Compensation, Stock Options, Activity

				Weighted
		Weighted		Average
		Average		Remaining		Aggregate
		Exercise		Contractual		Intrinsic
	Shares	Price		Terms		Value
Options outstanding as of December 31, 2023	17,336,362	$	11.37		7.86	$	11,391
Options exercisable as of December 31, 2023	8,288,944		11.84		6.18		7,250
Options unvested as of December 31, 2023	9,047,418		10.94		9.39		4,141
Granted	6,194,625		2.45		—		—
Exercised	(47,500)		2.09		—		—
Forfeited	(2,869,251)		15.98		—		—
Options outstanding as of September 30, 2024	20,614,236	$	8.07		7.35	$	476
Options exercisable as of September 30, 2024	8,733,294		11.56		5.63		342
Options unvested as of September 30, 2024	11,880,942	$	5.51		8.62	$	134

Market Condition Stock Option Awards

Schedule of Share-based Compensation, Stock Options, Activity

				Weighted
				Average
		Average		Remaining	Aggregate
		Exercise		Contractual	Intrinsic
	Shares	Price		Terms	Value
Options outstanding as of December 31, 2023	21,925,000	$	21.32	5.27	$	—
Options exercisable as of December 31, 2023	2,782,000		26.9	4.7		—
Options unvested as of December 31, 2023	19,143,000		20.50	5.35		—
Granted	2,952,500		2.42	—		—
Exercised	—		—	—		—
Forfeited	(12,311,500)		25.45	—		—
Options outstanding as of September 30, 2024	12,566,000	$	12.83	5.44	$	—
Options exercisable as of September 30, 2024	5,372,667		22.46	4.36		—
Options unvested as of September 30, 2024	7,193,333	$	5.63	6.24	$	—