Equity Incentive Plan

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Equity Incentive Plan

16. EQUITY INCENTIVE PLAN

2015 Equity

Incentive

Plan

Restricted stock units are converted into shares of the Company’s ordinary shares upon vesting

one-for-one

basis. The vesting of restricted stock unit is subject to the employee’s continuing service to the Company. The cost of these awards is determined using the fair value of the Company’s ordinary share on the date of the grant, and compensation is recognized on a straight-line basis over the requisite service period. The Company’s restricted stock units are

considered non-vested

share awards as defined under ASC 718.

On June 3, 2015, the Company adopted its 2015 Equity Incentive Plan (“the 2015 Plan”). The 2015 Plan provides for the grant of stock options, stock bonuses, restricted stock awards, restricted stock units and stock appreciation rights, which may be granted to employees (including officers), directors and consultants. The 2015 Plan reserved 20,000 thousand shares of ordinary shares for issuance upon exercise of stock options and restricted stock units.

Restricted Stock Units Activity

The following is a summary of, the 2015 Plan, which includes restricted stock units:


	Unit (in Thousands)
Available for grant at January 1, 2019		15,787
Restricted stock units granted		(1,584	)
Restricted stock units forfeited		57

Available for grant at December 31, 2019		14,260
Restricted stock units granted		(1,692	)
Restricted stock units forfeited		57

Available for grant at December 31, 2020		12,625
Restricted stock units granted		(2,326	)
Restricted stock units forfeited		134

Available for grant at December 31, 2021		10,433

The related tax effect for stock-based compensation benefit (expense) were US$(49) thousand, US$11 thousand and US$(155) thousand for 2019, 2020 and 2021, respectively. The related tax effect for

stock-based

compensation expense for restricted stock units exercised during 2019, 2020 and 2021 was US$3,446 thousand, US$2,188 thousand and US$2,767 thousand, respectively. The related tax effect was determined using applicable tax rates.

Restricted Stock Units

A summary of the status of restricted stock units and changes is as follows:


	Number of Non-vested Stock Units (in Thousands)			Weighted Average Grant Date Fair Value (US$)		Weight Average Remaining Recognition Period (Years)
Non-vested at January 1, 2019		1,621			13.85		0.38
Restricted stock units granted		1,584			8.01
Restricted stock units vested		(1,505	)		14.12
Restricted stock units forfeited		(57	)		9.59

Non-vested at December 31, 2019		1,643			8.08		0.29
Restricted stock units granted		1,692			9.40
Restricted stock units vested		(1,564	)		8.02
Restricted stock units forfeited		(57	)		9.31

Non-vested at December 31, 2020		1,714			9.37		0.31
Restricted stock units granted		2,326			17.62
Restricted stock units vested		(1,596	)		9.31
Restricted stock units forfeited		(134	)		14.99

Non-vested at December 31, 2021		2,310			17.37		1.57

As of December 31, 2021, there was US$24,807 thousand of total unrecognized compensation cost related to restricted stock units granted under the 2015 Plan.

Stock-based Compensation Expense

The following table shows total stock-based compensation expense included in the Consolidated Statements of Income for the years ended December 31, 2019, 2020 and 2021.


	Year Ended December 31
	2019		2020		2021
	US$		US$		US$
Cost of sales		305		253		389
Research and development		9,927		10,132		12,864
Sales and marketing		1,789		1,759		2,366
General and administrative		2,570		2,445		3,926

		14,591		14,589		19,545