
	For the Years Ended December 31,
(In millions)	2023		2022		2021
Research and development	$	296.7	$	98.5	$	89.3
Selling, general and administrative	371.7		175.1		169.5
Subtotal	668.4		273.6		258.8
Capitalized share-based compensation costs	(10.2)		(9.3)		(8.0)
Share-based compensation expense included in total cost and expense	658.2		264.3		250.8
Income tax effect	(132.6)		(49.2)		(46.7)
Share-based compensation expense included in net income attributable to Biogen Inc.	$	525.6	$	215.1	$	204.1

In connection with our acquisition of Reata in September 2023 we recognized Reata equity-based compensation expense, inclusive of employer taxes, of approximately $393.4 million attributable to the post-acquisition service period, of which $196.4 million was recognized as a charge to selling, general and administrative expense with the remaining $197.0 million as a charge to research and development expense within our consolidated statements of income for the year ended December 31, 2023. These amounts were associated with the accelerated vesting of stock options and RSUs previously granted to Reata employees that required no future services to vest. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to these consolidated financial statements.


	For the Years Ended December 31,
(In millions)	2023		2022		2021
Market stock units	$	4.9	$	13.2	$	45.6
Time-vested restricted stock units	220.0		202.3		159.8
Performance stock units settled in stock	35.5		35.0		23.9
Performance stock units settled in cash	6.8		10.1		12.2
Employee stock purchase plan	10.5		12.7		17.3
Stock options	3.7		0.3		—
Reata equity awards(1)	387.0		—		—
Subtotal	668.4		273.6		258.8
Capitalized share-based compensation costs	(10.2)		(9.3)		(8.0)
Share-based compensation expense included in total cost and expense	$	658.2	$	264.3	$	250.8

(1) Relates to the Reata equity-based compensation expense attributable to the post-acquisition service period, associated with the accelerated vesting of stock options and RSUs previously granted to Reata employees that required no future services to vest. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to these consolidated financial statements.

As of December 31, 2023, unrecognized compensation cost related to unvested share-based compensation was approximately $287.4 million, net of estimated forfeitures. We expect to recognize the cost of these unvested awards over a weighted-average period of 1.8 years.

We have three share-based compensation plans pursuant to which awards are currently being made: (i) the Biogen Inc. 2006 Non-Employee Directors Equity Plan (2006 Directors Plan); (ii) the Biogen Inc. 2017 Omnibus Equity Plan (2017 Omnibus Equity Plan); and (iii) the Biogen Inc. 2015 Employee Stock Purchase Plan (2015 ESPP).

In May 2006 our shareholders approved the 2006 Directors Plan for share-based awards to our directors. Awards granted from the 2006 Directors Plan may include stock options, shares of restricted stock, RSUs, stock appreciation rights and other awards in such amounts and with such terms and conditions as may be determined by a committee of our Board of Directors, subject to the provisions of the 2006 Directors Plan. We have reserved a total of 1.6 million shares of common stock for issuance under the 2006 Directors Plan. The 2006 Directors Plan provides that awards other than stock options and stock appreciation rights will be counted against the total number of shares reserved under the plan in a 1.5-to-1 ratio. In June 2015 our shareholders approved an amendment to extend the term of the 2006 Directors Plan until June 2025.

In June 2017 our shareholders approved the 2017 Omnibus Equity Plan for share-based awards to our employees. Awards granted from the 2017 Omnibus Equity Plan may include stock options, shares of restricted stock, RSUs, performance shares, stock appreciation rights and other awards in such amounts and with such terms and conditions as may be determined by a committee of our Board of Directors, subject to the provisions of the 2017 Omnibus Equity Plan. Shares of common stock available for grant under the 2017 Omnibus Equity Plan consist of 8.0 million shares reserved for this purpose, plus shares of common stock that remained available for grant under the Biogen Idec Inc. 2008 Omnibus Equity Plan (2008 Omnibus Equity Plan) as of June 7, 2017, or that could again become available for grant if outstanding awards under the 2008 Omnibus Equity Plan as of June 7, 2017, are cancelled, surrendered or terminated in whole or in part. The 2017 Omnibus Equity Plan provides that awards other than stock options and stock appreciation rights will be counted against the total number of shares available under the plan in a 1.5-to-1 ratio.

We have not made any awards pursuant to the 2008 Omnibus Equity Plan since our shareholders approved the 2017 Omnibus Equity Plan, and do not intend to make any awards pursuant to the 2008 Omnibus Equity Plan in the future, except that unused shares under the 2008 Omnibus Equity Plan have been carried over for use under the 2017 Omnibus Equity Plan.

In 2022 we granted approximately 81,000 stock options to our CEO (2022 CEO Grant) under the 2017 Omnibus Plan with a grant date fair value of $139.10 per option for a total of approximately $11.2 million. The fair value of the stock option grant is estimated as of the date of grant using a Black-Scholes option valuation model. The estimated fair value of the stock option is then expensed over the options' vesting periods. The 2022 CEO Grant is eligible to vest in equal annual installments over a three-year period from the grant date, subject to the CEO’s continued employment. The outstanding stock option has a 10-year term and is exercisable at a price per share not less than the fair market value of the underlying common stock on the date of grant.


	December 31, 2023
	Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term
Outstanding at December 31, 2022	81,000	$	301.85	9.9 years
Granted	—	—
Exercised	—	—
Forfeited	—	—
Outstanding at December 31, 2023	81,000	$	301.85	8.9 years
Exercisable at December 31, 2023	27,000	$	301.85	8.9 years

MSUs awarded to employees prior to 2014 vested in four equal annual increments beginning on the first anniversary of the grant date. Participants may ultimately earn between zero and 150.0% of the target number of units granted based on actual stock performance.

MSUs awarded to employees in 2014 and thereafter vest in three equal annual increments beginning on the first anniversary of the grant date, and participants may ultimately earn between zero and 200.0% of the target number of units granted based on actual stock performance.

The vesting of these awards is subject to the respective employee’s continued employment. The number of MSUs granted represents the target number of units that are eligible to be earned based on the attainment of certain market-based criteria involving our stock price. The number of MSUs earned is calculated at each annual anniversary from the date of grant over the respective vesting periods, resulting in multiple performance periods. Accordingly, additional MSUs may be issued or currently outstanding MSUs may be cancelled upon final determination of the number of awards earned.

We value grants of MSUs using a lattice model with a Monte Carlo simulation. This valuation methodology utilizes several key assumptions, the 30 calendar day average closing stock price on the date of grant for MSUs, expected volatility of our stock price, risk-free rates of return and expected dividend yield.


												December 31, 2021
Expected dividend yield												—%
Range of expected stock price volatility												54.8% - 61.6%
Range of risk-free interest rates												0.06% - 0.21%
30 calendar day average stock price on grant date												$262.23 - $360.31
Weighted-average per share grant date fair value												$358.77

During the first quarter of 2018 we began granting awards for performance-vested RSUs that will settle in stock. PSUs awarded to employees have a three-year performance period and vest on the third anniversary of the grant date. The vesting of these awards is subject to the respective employee’s continued employment. The number of PSUs granted represents the target number of units that are eligible to be earned based on the achievement of cumulative three-year performance measures established at the beginning of the performance period, which ends on December 31 of the third year of the performance period.

Beginning in 2022 we no longer grant MSUs as part of long term incentive program and have replaced with granting PSUs with a performance metric based on a three-year cumulative relative total shareholder return (rTSR) metric. The PSUs will vest on the third anniversary of the date of grant, with the number of PSUs earned based on this cumulative rTSR metric.


	December 31, 2023
	Shares	Weighted Average Grant Date Fair Value
Unvested at December 31, 2022	336,000	$	292.95
Granted (1)	206,000	383.61
Vested	(100,000)	290.72
Forfeited	(53,000)	323.52
Unvested at December 31, 2023	389,000	$	325.73

(1) PSUs settled in stock granted in 2023 include awards granted in conjunction with our annual awards made in February 2023 and PSUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.

We value grants of PSUs using a lattice model with a Monte Carlo simulation. This valuation methodology utilizes several key assumptions, the 30 calendar day average closing stock price on the date of grant for PSUs, expected volatility of our stock price, risk-free rates of return and expected dividend yield.


	For the Years Ended December 31,
	2023	2022
Expected dividend yield	—%	—%
Range of expected stock price volatility	44.7%	44.0% - 45.9%
Range of risk-free interest rates	4.1%	1.8% - 3.9%
30 calendar day average stock price on grant date	$283.93	$231.31 - $294.86
Weighted-average per share grant date fair value	$383.61	$294.43

During the first quarter of 2018 we began granting awards for performance-vested restricted stock units that will settle in cash. PSUs awarded to employees have three performance periods and vest on the third anniversary of the grant date. The vesting of these awards is subject to the respective employee’s continued employment. The number of PSUs granted represents the target number of units that are eligible to be earned based on the achievement of three annual performance measures established when the performance objectives are defined, which will be at the beginning of each year and will end on December 31 of such year.

Participants may ultimately earn between zero and 200.0% of the target number of PSUs granted based on the degree of achievement of the applicable performance metric. Accordingly, additional PSUs may be issued or currently outstanding PSUs may be cancelled upon final determination of the number of units earned. PSUs are classified as liability awards and will be settled in cash based on the 30 calendar day average closing stock price through the vesting date, once the actual vested and earned number of PSUs is determined. Since no shares are issued, these awards do not dilute equity.

RSUs awarded to employees generally vest no sooner than one-third per year over three years on the anniversary of the date of grant, or upon the third anniversary of the date of the grant, provided the employee remains continuously employed with us, except as otherwise provided in the plan. Shares of our common stock will be delivered to the employee upon vesting, subject to payment of applicable withholding taxes. RSUs awarded to directors for service on our Board of Directors vest on the first anniversary of the date of grant, provided in each case that the director continues to serve on our Board of Directors through the vesting date. Shares of our common stock will be delivered to the director upon vesting and are not subject to any withholding taxes.

(1) RSUs granted in 2023 primarily represent RSUs granted in conjunction with our annual awards made in February 2023 and awards made in conjunction with the hiring of new employees. RSUs granted in 2023 also include approximately 7,300 RSUs granted to our Board of Directors.