Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2021

Stockholders' Equity [Abstract]

Stock Option Activity

The following table summarizes the stock option activity under our stock plans for the year ended December 31, 2021 (in thousands, except per share and contractual life data):

	Number of Shares			Weighted Average Exercise Price Per Share		Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding at December 31, 2020		12,439		$	54.11
Granted		3,382		$	53.07
Exercised		(219	)	$	38.69
Cancelled/forfeited/expired		(1,513	)	$	54.65
Outstanding at December 31, 2021		14,089		$	54.04		3.89	$	1,131
Exercisable at December 31, 2021		9,175		$	53.65		2.94	$	1,067

RSU Activity

The following table summarizes the RSU activity for the year ended December 31, 2021 (in thousands, except per share data):

	Number of Shares			Weighted Average Grant Date Fair Value Per Share
Non-vested at December 31, 2020		2,374		$	58.81
Granted		1,548		$	57.69
Vested		(834	)	$	57.47
Cancelled/forfeited		(411	)	$	59.24
Non-vested at December 31, 2021		2,677		$	58.51

Stock-Based Compensation Expense

The following table summarizes stock-based compensation expense for the years ended December 31, 2021, 2020 and 2019 (in thousands):

	Year Ended December 31,
	2021		2020		2019
Cost of sales	$	456	$	1,991	$	438
Research, development and patent		87,522		115,584		95,348
Selling, general and administrative		32,700		112,542		50,788
Total	$	120,678	$	230,117	$	146,574

Weighted-Average Assumptions for Stock Options

Ionis Employee Stock Options:

	Year Ended December 31,
	2021			2020			2019
Risk-free interest rate		0.6	%		1.5	%		2.3	%
Dividend yield		0.0	%		0.0	%		0.0	%
Volatility		54.0	%		58.6	%		60.3	%
Expected life	4.9 years			4.7 years			4.8 years

Ionis Board of Director Stock Options:

	Year Ended December 31,
	2021			2020			2019
Risk-free interest rate		1.2	%		0.5	%		1.9	%
Dividend yield		0.0	%		0.0	%		0.0	%
Volatility		55.9	%		57.6	%		60.7	%
Expected life	7.3 years			6.7 years			6.6 years

Weighted-Average Assumptions for ESPP

Ionis ESPP:

	Year Ended December 31,
	2021			2020			2019
Risk-free interest rate		0.1	%		0.8	%		2.4	%
Dividend yield		0.0	%		0.0	%		0.0	%
Volatility		42.4	%		47.9	%		45.6	%
Expected life	6 months			6 months			6 months