Employee Benefit Plans (Tables)

3 Months Ended

Mar. 31, 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
	March 31, 2024		March 31, 2023
Cost of sales	$	2,006	$	2,677
Research and development		2,342		2,283
Selling, general and administrative		6,023		35,221
	$	10,371	$	40,181

Nonvested Restricted Stock Shares Activity

The following table reflects the restricted stock and restricted stock unit activity for the three months ended March 31, 2024 (in thousands except share amounts):

		Weighted		Aggregate
		Average Grant Date		Intrinsic
	Shares	Fair Value		Value
Unvested restricted stock and restricted stock units at December 31, 2023	6,732,884	$	15.66	$	30,298
Granted	17,000		5.23		—
Vested	(230,675)		28.42		—
Forfeited	(604,353)		18.69		—
Unvested restricted stock and restricted stock units at March 31, 2024	5,914,856	$	14.82	$	20,347

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 at December 31, 2023	17,336,362	$	11.37		7.86	$	11,391
Options exercisable at December 31, 2023	8,288,944		11.84		6.18		7,250
Options unvested at December 31, 2023	9,047,418		10.94		9.39		4,141
Granted	313,000		3.28		—		—
Exercised	(20,000)		2.10		—		—
Forfeited	(920,300)		19.42		—		—
Options outstanding at March 31, 2024	16,709,062	$	10.79		7.60	$	3,858
Options exercisable at March 31, 2024	8,334,755		11.93		5.90		3,792
Options unvested at March 31, 2024	8,374,307	$	9.65		9.29	$	66

Performance Stock Option Awards

Schedule of Share-based Compensation, Stock Options, Activity

				Weighted
		Weighted		Average
		Average		Remaining	Aggregate
		Exercise		Contractual	Intrinsic
	Shares	Price		Terms	Value
Options outstanding at December 31, 2023	21,925,000	$	21.32	5.27	$	—
Options exercisable at December 31, 2023	2,782,000		26.9	4.7		—
Options unvested at December 31, 2023	19,143,000		20.50	5.35		—
Granted	—		—	—		—
Exercised	—		—	—		—
Forfeited	(2,250,000)		—	—		—
Options outstanding at March 31, 2024	19,675,000	$	21.44	4.95	$	—
Options exercisable at March 31, 2024	2,782,000		26.92	4.48		—
Options unvested at March 31, 2024	16,893,000	$	20.54	5.03	$	—