As of December 31, 2021, an aggregate of approximately 44.5 million unissued shares was authorized for future issuance under the Company’s stock plans, which primarily includes shares issuable under the 2017 Equity Incentive Plan (2017 EIP) and the ESPP. Under the 2017 EIP, shares issued and outstanding under the Amended and Restated 2006 Share Incentive Plan (the 2006 Share Incentive Plan) and the 2017 Equity Incentive Plan that expire or are forfeited generally become available for future issuance under the 2017 Equity Incentive Plan. No additional awards will be granted under the 2006 Share Incentive Plan; however, there are vested and unvested awards outstanding under the 2006 Share Incentive Plan. The Company’s stock-based compensation plans are administered by the Company’s Board of Directors (the Board), or designated Committee thereof, which selects persons to receive awards and determines the number of shares subject to each award and the terms, conditions, performance measures and other provisions of the awards. See Note 1 to these Consolidated Financial Statements for discussion regarding the valuation of equity awards.

The 2017 Equity Incentive Plan provides for awards of RSUs and stock options as well as other forms of equity compensation. Stock option awards granted to employees generally vest over a four-year period on a cliff basis 12 months after the grant date and then monthly thereafter. The contractual term of stock option awards is generally 10 years from the grant date. RSUs granted to employees generally vest annually over a straight-line four-year period after the grant date. PRSUs generally vest

The ESPP was initially approved in June 2006, replacing the Company’s previous plan, and was most recently amended in June 2019. Under BioMarin’s ESPP, employees meeting specific employment qualifications are eligible to participate and can purchase shares on established dates (each purchase date) semi-annually through payroll deductions at the lower of 85% of the fair market value of the stock at the commencement of the offering period or each purchase date of the offering period. Each offering period will span up to two years. The ESPP permits eligible employees to purchase common stock through payroll deductions for up to 10% of qualified compensation, up to an annual limit of $25,000. The ESPP is intended to qualify as an “employee stock purchase plan” under Section 423 of the Internal Revenue Code. During the year ended December 31, 2021, the Company issued 0.3 million shares under the ESPP. As of December 31, 2021, approximately 7.0 million shares were authorized and 3.1 million shares reserved for future issuance under the ESPP.

On the date of the Company’s annual meeting of stockholders for a given year, each re-elected Independent Director receives an RSU grant valued at $400,000, with the number of RSUs to be granted calculated based on the three-month trailing average closing price of the Company’s common stock on the Nasdaq Global Select Market. The annual RSU grant for a director who has served for less than a year is prorated to the nearest quarter of the calendar year. The RSUs subject to the annual award vest in full on the one-year anniversary of the grant date, subject to each respective Director providing service to the Company through such vesting date. Upon election or appointment, a new Independent Director will receive an RSU grant on the same terms as the annual award, pro-rated for amount and vesting to the nearest quarter for the time such new Independent Director will serve prior to the Company’s next annual meeting of stockholders.


	Years Ended December 31,
	2021		2020		2019
Cost of sales	$	22,357	$	26,246	$	16,146
Research and development	67,196		61,942		56,649
Selling, general and administrative	107,710		101,523		87,070
Total stock-based compensation expense	$	197,263	$	189,711	$	159,865

Stock-based compensation of $20.0 million, $20.1 million and $20.3 million was capitalized into inventory for the years ended December 31, 2021, 2020 and 2019, respectively. Capitalized stock-based compensation is recognized in Cost of Sales when the related product is sold.


	Shares	Weighted Average Grant Date Fair Value
Non-vested units as of December 31, 2020	4,173,124	$	83.41
Granted	2,338,270	$	78.46
Vested	(1,499,408)	$	85.74
Forfeited	(574,474)	$	80.57
Non-vested units as of December 31, 2021	4,437,512	$	80.38

The weighted-average grant date fair value per share of RSUs granted during the years ended December 31, 2021, 2020 and 2019, was $78.46, $77.13 and $91.28, respectively. The total intrinsic value of restricted stock that vested and released in the years ended December 31, 2021, 2020 and 2019, was $117.2 million, $109.9 million and $101.0 million respectively.

Revenue PRSUs: Although no PRSUs with vesting conditions based on revenue performance were granted during the year ended December 31, 2021 or 2020, awards granted during prior periods presented were contingent upon the achievement of an annual revenue target and the earned RSUs vest over a three-year service period. The number of shares that may be earned ranged between 50% and 200% of the base RSUs, depending on the percentage of the respective annual year's Net Product Revenues, excluding net revenues attributable to Aldurazyme, and determined using fixed foreign currency exchange rates achieved against the target, with a threshold achievement level of 75% of target and a ceiling achievement level of 125% of target.

The weighted-average grant date fair value of Revenue PRSUs granted during the year ended December 31, 2019, was $94.53. As of December 31, 2021, total unrecognized compensation expense of $0.4 million related to Revenue PRSUs was expected to be recognized over a weighted average period of approximately three months.


	Shares	Weighted Average Grant Date Fair Value
Non-vested units as of December 31, 2020	220,665	$	83.83
Granted	234,120	$	78.09
Vested	(8,310)	$	116.83
Forfeited	(40,004)	$	61.09
Non-vested units as of December 31, 2021	406,471	$	70.82

Non-vested Other PRSUs included grants with vesting contingent upon the achievement of a three-year Non-GAAP income target and grants with vesting contingent upon achievement of a three-year strategic goal target. The awarded PRSUs, if any, vest ratably over a three-year service period. The Company evaluated the targets in the context of its current long-range financial plan, its product candidate development pipeline and planned regulatory activity and determined that attainment of each grant target was probable for accounting purposes commencing in the quarter granted. The number of shares that may be earned range between 50% and 200% of the base RSUs.

Also included in non-vested Other PRSUs were awards that vest contingent upon achievement of certain regulatory milestones some of which, for accounting purposes, were deemed not yet probable of vesting as of December 31, 2021. Therefore, as of December 31, 2021, total unrecognized compensation expense of $10.9 million related to awards deemed probable of vesting and $10.6 million related to awards not yet deemed probable of vesting. The expected weighted average period over which expense is to be recognized for the awards that are considered probable of vesting as of December 31, 2021 was 1.7 years.

The Compensation Committee and Board may grant RSUs with market-based vesting conditions (base TSR-RSUs) to certain executives. These base TSR-RSUs vest, if at all, in full following a three-year service period only if certain total shareholder return (TSR) results relative to the Nasdaq Biotechnology Index comparative companies are achieved. The number of shares that may be earned range between zero percent and 200% of the base TSR-RSUs with a ceiling achievement level of 100% of the base TSR-RSUs in the event the Company’s TSR is above the 50th percentile but negative on an absolute basis.


	Shares	Weighted Average Grant Date Fair Value
Non-vested units as of December 31, 2020	220,990	$	127.23
Granted	141,610	$	117.52
Vested	—	$	—
Forfeited	(11,740)	$	114.94
Non-vested units as of December 31, 2021	350,860	$	123.73


	Years Ended December 31,
	2021	2020	2019
Grant date fair value	$117.52	$112.12 – $217.65	$143.92
Expected volatility	24.7% – 161.7%	21.3% – 159.9%	21.7% – 155.6%
Dividend yield	0.0%	0.0%	0.0%
Expected term	2.8 years	2.5 – 2.8 years	2.8 years
Risk-free interest rate	0.3%	0.2 – 0.4%	2.4%

The following table summarizes activity under the Company’s stock option plans for the year ended December 31, 2021. All stock option grants presented in the table had exercise prices not less than the fair value of the underlying common stock on the grant date:


	Shares	Weighted Average Exercise Price		Weighted Average Remaining Years	Aggregate Intrinsic Value (1)
Options outstanding as of December 31, 2020	6,829,437	$	73.19		$	119,607
Granted	665,610	$	78.33
Exercised	(892,890)	$	34.99
Expired and forfeited	(152,465)	$	82.26
Options outstanding as of December 31, 2021	6,449,692	$	78.79	4.8	$	80,857
Options unvested as of December 31, 2021	1,287,835	$	79.82	8.6	$	12,334
Exercisable at December 31, 2021	5,161,857	$	78.54	3.8	$	68,523

(1)The aggregate intrinsic value for outstanding options is calculated as the difference between the exercise price of the underlying awards and the quoted price of the Company’s common stock on the Nasdaq Global Select Market as of the last trading day for the respective year. The aggregate intrinsic value of options outstanding and exercisable includes options with an exercise price below $88.35, the closing price of the Company’s common stock on the Nasdaq Global Select Market on December 31, 2021.

The weighted-average fair value per stock option granted in the years ended December 31, 2021, 2020 and 2019, were $31.61, $27.47 and $36.84, respectively. The total intrinsic value of options exercised during the years ended December 31, 2021, 2020 and 2019, was $40.7 million, $71.9 million and $32.5 million, respectively, determined as of the date of option exercise. Upon the exercise of the options, the Company issues new common stock from its authorized shares.

Years Ended December 31,

2021

2020

2019

Expected volatility

39.4 – 41.6%

36.5 – 42.2%

37.1 – 37.4%

Dividend yield

0.0%

Expected term

4.7 – 6.0 years

4.6 – 5.9 years

4.6 – 5.8 years

Risk-free interest rate

0.7 – 1.3%

0.3 – 1.7%

2.2 – 3.0%

As of December 31, 2021, total unrecognized compensation cost related to unvested stock options of $31.3 million was expected to be recognized over a weighted average period of 2.5 years. The net tax expense from stock options exercised during the year ended December 31, 2021 was $0.5 million.

Years Ended December 31,

2021

2020

2019

Expected volatility

23.7 – 69.2%

30.6 – 69.2%

27.7% – 35.0%

Dividend yield

0.00%

Expected term

0.5 – 2.0 years

Risk-free interest rate

0.04% – 2.4%

0.1 – 2.8%

1.2 – 2.8%