The Company’s share-based compensation plans are intended to attract and retain employees and to provide an incentive for them to assist the Company to achieve long-range performance goals and to enable them to participate in long-term growth of the Company. The Company settles restricted stock unit awards, employee stock purchase option exercises and stock option exercises with newly issued common shares.

Onto Innovation Inc. 2020 Stock Plan (the “2020 Plan”). The 2020 Plan provides for the grant of 3,744 stock options and other stock awards to employees, directors and consultants at an exercise price equal to the fair market value of the common stock on the date of grant. Options granted under the 2020 Plan typically grade vest over a three-year period and expire ten years from the date of grant. Restricted stock units granted under the 2020 Plan typically vest over a three-year period for employees and one year for directors; however, other vesting periods are allowable under the 2020 Plan. Restricted stock units (“RSU”) granted to employees have time based or performance-based vesting. As of January 1, 2022, there were 3,376 shares of common stock available for issuance pursuant to future grants under the 2020 Plan.

Onto Innovation Inc. 2020 Employee Stock Purchase Plan (the “2020 ESPP”). Under the terms of the 2020 ESPP, eligible employees may have up to 10 % of eligible compensation deducted from their pay and applied to the purchase of shares of Company common stock. The price the employee pays for each share of stock is 85 % of the lesser of the fair market value of Company common stock at the beginning or the end of the applicable six-month purchase period. The 2020 ESPP is intended to qualify under Section 423 of the Internal Revenue Code and is a compensatory plan as defined by FASB ASC 718, “Stock Compensation.” Through the Company’s employee stock purchase plans, employees purchased 242, 91 and 72 shares during the twelve months ended January 1, 2022, December 26, 2020 and December 31, 2019, respectively. As of January 1, 2022 and December 26, 2020, there were 1,258 and 1,500, shares available for issuance under the Company’s employee stock purchase plan, respectively.

	Year Ended
	January 1, 2022			December 26, 2020			December 31, 2019
Share-based compensation expense:
Restricted stock units, including all performance and market based awards	$	17,174		$	15,780		$	10,421
Stock options and employee stock purchase options		2,368			1,882			164
Total share-based compensation		19,542			17,662			10,585
Tax effect on share-based compensation		4,255			3,849			2,283
Net effect on net income	$	15,287		$	13,813		$	8,302
Effect on earnings per share:
Basic	$	(0.31	)	$	(0.28	)	$	(0.28	)
Diluted	$	(0.31	)	$	(0.28	)	$	(0.28	)

During the fiscal years 2021, 2020, and the 2019 calendar year, the Company issued both service-based RSUs and market-based performance RSUs (“PRSUs”). Service-based RSUs typically vest over a period of 3 years or less. Market-based PRSUs generally vest three years from the grant date if certain performance criteria are achieved and require continued employment. Based upon the terms of such awards, the number of shares that can be earned over the performance periods is based on the Company’s Common Stock price performance compared to the market price performance of a designated benchmark index, ranging from 0% to 200% of target. The designated benchmark index was the Philadelphia Semiconductor Sector Index for market-based PRSUs issued in 2021 and 2020. The designated benchmark was a peer group in 2019. The stock price performance or market price performance is measured using the closing price for the 20-trading days prior to the dates the performance period begins and ends.

The following table summarizes the Company’s combined service-based RSUs and market-based PRSUs:

	Number of Shares			Weighted Average Grant Date Fair Value
Nonvested at December 31, 2018		639		$	24.26
Granted		271		$	29.58
Assumed in Merger		598		$	31.43
Vested		(366	)	$	25.69
Forfeited		(35	)	$	26.44
Nonvested at December 31, 2019		1,107		$	28.89
Granted		498		$	34.71
Vested		(498	)	$	29.46
Forfeited		(143	)	$	29.99
Nonvested at December 26, 2020		964		$	31.37
Granted		338		$	69.82
Vested		(441	)	$	30.90
Forfeited		(96	)	$	42.40
Nonvested at January 1, 2022		765		$	48.25

Of the 765 shares outstanding at January 1, 2022, 667 are service-based RSUs and 98 are market-based PRSUs. The fair value of the Company’s service-based RSUs was calculated based on the fair market value of the Company’s stock at the date of grant. The fair value of the Company’s market-based PRSUs granted during fiscal years 2021, 2020, and 2019 was calculated using a Monte Carlo simulation model at the date of the grant, resulting in a weighted average grant-date fair value per share of $80.04, $47.86, and $21.49, respectively.

As of January 1, 2022, there was $21,019 of total unrecognized compensation cost related to restricted stock units granted under the plans. That cost is expected to be recognized over a weighted average period of 1.5 years.

The Company did not grant any stock options during fiscal years 2021, 2020 and 2019. As of January 1, 2022, there were 2 stock options outstanding and exercisable with a weighted average exercise price of $15.20, and aggregate intrinsic value of $191 and a contract term that will expire within one year. The total intrinsic value of the stock options exercised during fiscal years 2021, 2020 and 2019 was $1,365, $420 and $51, respectively.

The Company has a 401(k) savings plan that allows employees to contribute up to 100% of their annual compensation to the Plan on a pre-tax or after-tax basis, limited to a maximum annual amount as set periodically by the Internal Revenue Service. The plan provides a 50% match of all employee contributions up to 6 percent of the employee’s salary. Matching contributions to the plan totaled $2,544, $2,315 and $1,317 for the years ended January 1, 2022, December 26, 2020 and December 31, 2019, respectively.