Equity

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Equity

(6) Equity

Common Stock

There was no common stock activity during the three months ended March 31, 2023 and 2022 except as described in Incentive Equity Awards below.

Incentive Equity Awards

The following table summarizes the aggregate number of stock options and restricted stock units, or RSUs, outstanding under the Amarin Corporation plc 2020 Stock Incentive Plan, or the 2020 Plan, as of March 31, 2023:

	March 31, 2023
Outstanding stock options		19,638,850
% of outstanding shares on a fully-diluted basis		4	%
Outstanding RSUs		18,203,692
% of outstanding shares on a fully-diluted basis		4	%

The following table represents equity awards activity during the three months ended March 31, 2023 and 2022:

	Three months ended March 31,
	2023		2022
Common shares issued for stock option exercises		1,232,263		10,602
Gross and net proceeds from stock option exercises	$	1,871,758	$	30,000
Common shares issued in settlement of vested RSUs		2,270,674		493,381
Shares retained for settlement of employee tax obligations ─ RSUs		716,438		161,083
Common shares issued in settlement of vested Performance-based RSUs (1)		244,274		—
Shares retained for settlement of employee tax obligations ─ Performance-based RSUs		111,085		—

(1)Performance-based RSUs vested in connection with the achievement of certain sales performance conditions on February 21, 2023. These performance-based RSUs will vest over a three-year period based on continuous service from the grant date.

In February 2023, the Company granted a total of 7,775,850 RSUs and 4,297,500 stock options to employees under the 2020 Plan. The RSUs vest annually over a three-year period and the stock options vest quarterly over a four-year period with a one-year cliff vesting. Also in February 2023, the Company granted a total of 1,368,800 RSUs to employees under the 2020 Plan that vest upon the achievement of specified sales and operational performance conditions.

In February 2022, the Company granted a total of 5,987,500 RSUs and 1,976,600 stock options to employees under the 2020 Plan. The RSUs vest annually over a three-year period and the stock options vest quarterly over a four-year period with a one-year cliff vesting. Also in February 2022, the Company granted a total of 1,089,500 RSUs to employees under the 2020 Plan that vest upon the achievement of specified sales and operational performance conditions.

In January 2022, the Company granted a total of 81,082 RSUs and 103,569 stock options to newly appointed members of the Company’s Board of Directors under the 2020 Plan and in accordance with the Company's non-employee Director compensation policy. The RSUs vest in equal installments over a three-year period upon the anniversary of the grant date, and are subject to deferred settlement upon the Director’s separation of service with the Company. The stock options vested in full upon the one-year anniversary of the grant date. Upon termination of service to the Company or upon a change of control as defined in the 2020 Plan, each Director

shall be entitled to a payment equal to the fair market value of one share of Amarin common stock per award vested or granted, respectively, which is required to be made in shares.