In April 2006, the Company adopted the 2006 Long Term Incentive Plan (the “2006 Plan”). The 2006 Plan provides for the granting of stock options, stock appreciation rights, restricted stock, restricted stock units (“RSU”) performance awards and other stock awards, to eligible directors, employees and consultants of the Company. The Company’s 2006 Plan expired on April 13, 2016 by its terms. No further equity awards can be granted under the 2006 Plan. Outstanding awards under the 2006 Stock Plan remain subject to the terms and conditions of the 2006 Plan.

In April 2016, the Company’s Board of Directors adopted the 2016 Equity Incentive Plan (the “2016 Plan”) which was approved by the Company’s stockholders at the 2016 Annual Meeting of Stockholders on June 3, 2016. The 2016 Plan provides for the granting of stock options, stock appreciation rights, restricted stock, RSUs, performance shares and performance units to eligible directors, employees and consultants of the Company. The original maximum aggregate number of shares that could be issued under the 2016 Plan was 2.5 million shares, plus (i) any shares that were available for grant under the Company’s 2006 Plan as of immediately prior to the 2006 Plan’s expiration by its terms, which was 699,827 shares, plus (ii) any shares granted under the 2006 Plan that expire, are forfeited to or repurchased by the Company. In May 2018, the Company adopted amendments to the 2016 Plan which increased the number of shares of the Company’s common stock that may be issued under the 2016 Plan by an additional 1.7 million shares. In January 2019, the Company received the approval from its Compensation Committee to increase the number of shares that the Company may be issued under the 2016 Plan to a new total of 3.1 million shares, pursuant to the adjustment provisions of the 2016 Plan. In May 2020, the Company adopted amendments to the 2016 Plan which increased the number of shares of the Company’s common stock that may be issued under the 2016 Plan by an additional 2.0 million shares. In June 2023, the Company's stockholders approved amendments to the 2016 Plan which increased the number of shares of the Company’s common stock that may be issued under the 2016 Plan by an additional 2.0 million shares. As of December 31, 2024, approximately 2.3 million shares remained available for future grants under the 2016 Plan.

Options granted generally vest over four years with the first tranche at the end of twelve months from the date of grant and the remaining shares vesting monthly over the remaining three years. Options granted generally expire in 10 years from the date of grant. RSUs granted generally vest in annual installments over four years or over three years with the first tranche at the end of twelve months from the vest start date and the remaining vesting quarterly over the remaining two years. RSUs do not have an expiration date. Performance shares granted generally vest at the end of a three-year period if performance conditions are met and do not have an expiration date.

Any shares that are tendered by a participant of the 2016 Plan or retained by the Company as full or partial payment to the Company for the purchase of an award or to satisfy tax withholding obligations in connection with an award shall no longer again be made available for issuance under the 2016 Plan.

In February 2024, the Company adopted the 2024 Inducement Equity Incentive Plan (the “2024 Inducement Plan”), which was approved by the Company’s Board of Directors on February 9, 2024. The 2024 Inducement Plan provides for the granting of stock options, stock appreciation rights, restricted stock, RSUs, performance shares and performance units to eligible individuals who are entering into employment with the Company. The original maximum aggregate number of shares that could be issued under the 2024 Inducement Plan was 2.0 million shares. As of December 31, 2024, approximately 0.2 million shares were reserved for future grants under the 2024 Inducement Plan.

The Company sponsors an Employee Stock Purchase Plan (the “ESPP”), pursuant to which eligible employees may contribute up to 10% of compensation, subject to certain income limits, to purchase shares of the Company’s common stock. The terms of the plan include a look-back feature that enables employees to purchase stock semi-annually at a price equal to 85% of the lesser of the fair market value at the beginning of the offering period and the purchase date. The duration of each offering period is generally six-months. In April 2022, the Company approved an amendment to the plan to increase the number of shares of common stock authorized for sale under the plan by 1.0

million shares to a total of 3.0 million shares. For the years ended December 31, 2024, 2023, and 2022, the Company recognized ESPP compensation expense of $1.2 million, $1.1 million and $1.3 million, respectively. Approximately 312,000 shares of common stock were purchased at an average exercise price of $11.44 in the year ended December 31, 2024. As of December 31, 2024, approximately 0.5 million shares were reserved for future issuance under the ESPP.

Stock option activity was as follows:


(In thousands, except per share amounts)	Number of Shares			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding as of December 31, 2023		866		$	30.70
Exercised		(163	)	$	24.57
Expired		(228	)	$	31.15
Outstanding as of December 31, 2024		475		$	32.60		1.42	$	367,881

As of December 31, 2024
Vested and expected to vest		475		$	32.60		1.42	$	367,881
Exercisable Options		475		$	32.60		1.42	$	367,881

The aggregate intrinsic values in the table above represent the total pre-tax intrinsic values (the difference between the Company’s closing stock price on the last trading day of 2024, or December 31, 2024, and the exercise price, multiplied by the number of shares underlying the in-the-money options) that would have been received by the option holders had all option holders exercised their options on December 31, 2024. This amount changes based on the fair market value of the Company’s stock. Total intrinsic value of options exercised for the years ended December 31, 2024 and 2022 was $0.4 million and $0.2 million, respectively. There were no options exercised for the year ended December 31, 2023.

The total fair value of options vested during the years ended December 31, 2023, and 2022 was $0.7 million and $1.3 million, respectively. There were no options vested during the year ended December 31, 2024.

The following table summarizes significant ranges of outstanding and exercisable stock options as of December 31, 2024:


	Options Outstanding						Options Exercisable
Range of Exercise Prices	Shares Outstanding		Weighted- Average Remaining Contractual Life		Weighted- Average Exercise Price Per Share		Shares Exercisable		Weighted- Average Exercise Price Per Share
	(In thousands)		(In years)		(In dollars)		(In thousands)		(In dollars)
$23.48 - $23.48		3		1.23	$	23.48		3	$	23.48
$25.37 - $25.37		5		2.42	$	25.37		5	$	25.37
$26.61 - $26.61		271		1.42	$	26.61		271	$	26.61
$38.32 - $38.32		25		3.59	$	38.32		25	$	38.32
$41.67 - $41.67		171		1.07	$	41.67		171	$	41.67
$23.48 - $41.67		475		1.42	$	32.60		475	$	32.60

RSU activity was as follows:


(In thousands, except per share amounts)	Number of Shares			Weighted Average Grant Date Fair Value Per Share		Weighted Average Remaining Contractual Term		Average Intrinsic Value
Outstanding as of December 31, 2023		1,567		$	22.83
Granted		1,939		$	15.91
Vested		(739	)	$	23.50
Cancelled		(217	)	$	19.66
Outstanding as of December 31, 2024		2,550		$	17.64		1.20	$	71,060

The total fair value of RSUs vested during the years ended December 31, 2024, 2023 and 2022 was $11.0 million, $9.2 million and $14.6 million, respectively. The grant date fair value of RSUs vested during the years ended December 31, 2024, 2023 and 2022 was $17.4 million, $17.8 million and $21.5 million, respectively.

Since 2020, the Company’s executive officers were granted performance-based restricted stock units (“PSUs”) under the 2016 Plan with vesting occurring at the end of a three-year period if performance conditions are met. In February 2024, the Company granted PSUs under the 2024 Inducement Plan to its newly-hired Chief Executive Officer with 1/3 of the target PSUs being allocated to each tranche and vesting occurring at the end of each anniversary of the vesting commencement date over a three-year period. In addition, in 2024, the Company granted PSUs under the 2024 Inducement Plan to its newly-hired employees with vesting occurring at the end of a three-year period if performance conditions are met. The number of PSUs earned and eligible to vest are determined based on achievement of the pre-determined performance or market conditions and the recipients’ continued service with the Company. The number of PSUs to vest could range from 0% to 150% of the target shares granted. For PSUs with a performance condition, at the end of each reporting period, the Company evaluates the probability of achieving the performance conditions and records the related stock-based compensation expense based on performance to date over the service period. The stock-based compensation expense relating to PSUs with a market condition is recognized ratably from the service inception date to the vesting date for each tranche.


(In thousands, except per share amounts)	Number of Shares			Weighted Average Grant Date Fair Value Per Share
Outstanding as of December 31, 2021		293		$	33.07
Granted		145		$	22.37
Vested		—		$	—
Cancelled		(8	)	$	27.17
Outstanding as of December 31, 2022		430		$	29.38
Granted		145		$	14.44
Vested		—		$	—
Cancelled		(158	)	$	27.85
Outstanding as of December 31, 2023		417		$	24.76
Granted		630		$	21.00
Vested		—		$	—
Cancelled		(392	)	$	25.12
Outstanding as of December 31, 2024		655		$	20.93

The Company measures stock-based compensation at the grant date based on the estimated fair value of the award. Estimated compensation cost relating to time-based RSUs and PSUs with a performance condition is based on

the closing fair market value of the Company’s common stock on the date of grant. The grant date fair value for PSUs with a market condition is determined using the Monte Carlo valuation method. The fair value of options granted and the purchase rights granted under the ESPP is estimated on the date of grant using a Black-Scholes-Merton option valuation model that uses the assumptions noted in the following table. The estimated expected term of options granted is derived from historical data on employee exercise and post-vesting employment termination behavior. The risk-free interest rate of options granted and the purchase rights granted under the ESPP is based on the implied yield currently available on U.S. Treasury securities with a remaining term commensurate with the estimated expected term. Expected volatility of options granted under the 2016 Plan and the purchase rights granted under the ESPP is based on historical volatility over the most recent period commensurate with the estimated expected term. The Company has never declared or paid cash dividends on its capital stock and does not anticipate paying cash dividends in the foreseeable future.

No stock options were granted during the years ended December 31, 2024, 2023 and 2022. The following table sets forth the weighted-average assumptions used to estimate the fair value of purchase rights granted under the ESPP:


	Year Ended December 31,
	2024			2023			2022

Expected life (in years)		0.5			0.5			0.5
Risk-free interest rate		5.01	%		5.19	%		2.25	%
Expected volatility		48.1	%		35.8	%		39.6	%
Dividend yield		—			—			—

The following table sets forth the stock-based compensation expense resulting from stock options, time-based and performance-based RSUs and the ESPP included in the Company’s consolidated statements of operations:


	Year Ended December 31,
(In thousands)	2024		2023		2022
Cost of revenue	$	1,613	$	1,405	$	1,353
Research and development		3,297		3,935		4,177
Sales and marketing		6,182		5,336		5,603
General and administrative		11,586		7,262		6,601
Total	$	22,678	$	17,938	$	17,734

Total stock-based compensation cost capitalized in inventory was less than $0.9 million as of each of the years ended December 31, 2024, 2023 and 2022, respectively.

As of December 31, 2024, $42.8 million of unrecognized compensation cost related to unvested time-based and performance-based RSUs is expected to be recognized over a weighted-average period of 2.1 years. If there are any modifications or cancellations of the underlying unvested awards, the Company may be required to accelerate, increase or cancel all or a portion of the remaining unearned stock-based compensation expense.