The Company has stock-based compensation plans under which it grants stock options, restricted stock units ("RSUs"), and performance restricted stock units ("PRSUs") to officers, directors and third parties. Total stock-based compensation for the periods presented is as follows (in thousands):


	Three Months Ended
	March 31,
	2026		2025
Cost of sales	$	970	$	3,043
Research and development		4,001		3,644
Sales, general and administrative		18,688		15,631
Total	$	23,659	$	22,318

As of March 31, 2026, there was $115.3 million of unrecognized compensation expense for RSUs and PRSUs to be recognized over a weighted average period of 2.2 years.

The Company issued approximately 4,324,680 and 3,521,532 shares of common stock, before net share settlement, upon vesting of RSUs and PRSUs during the three months ended March 31, 2026 and 2025, respectively.

Employees are eligible to participate in the Employee Stock Purchase Plan ("ESPP") approved by its shareholders. During the three months ended March 31, 2026 and 2025, there were no shares issued under the ESPP.

The Company estimates the fair value of shares issued to employees under the ESPP using the Black-Scholes option-pricing model. The assumptions used to estimate the fair value of stock options granted and stock purchase rights under the ESPP are as follows:


	Three Months Ended
	March 31,
	2026			2025
Risk-free interest rate		3.81	%	4.44%
Expected dividend yield		—			—
Expected term (years)		0.50			0.50
Volatility		55.85	%		91.91	%

In connection with debt financing entered into with Squadron Medical Finance Solutions, LLC ("Squadron Medical") in 2018, and amended in 2019 and 2020, the Company issued common stock warrants to Squadron Medical and a participant lender (the “Squadron Medical Warrants”). The Squadron Medical Warrants expire in May 2027 and are exercisable by cash or cashless exercise. No Squadron Medical Warrants have been exercised as of March 31, 2026.

The Company issued warrants to its Chairman and Chief Executive Officer (the “Executive Warrants”). The Executive Warrants had a nine-year term and are exercisable by cash or cashless exercise. No Executive Warrants have been exercised as of March 31, 2026.

A summary of all outstanding warrants for common stock as of March 31, 2026, is as follows (in thousands, except for strike price data):


	Number of Warrants		Strike Price		Expiration
2018 Squadron Medical Warrants		845	$	3.15	May 2027
2019 Squadron Medical Warrants		4,839	$	2.17	May 2027
2020 Squadron Medical Warrants		1,076	$	4.88	May 2027
Executive Warrants		1,327	$	5.00	December 2026
Other1		90	$	12.15	Various through December 2030
Total		8,177

(1)

Weighted-average strike price.

All outstanding warrants were deemed to qualify for equity classification under authoritative accounting guidance.