The Company maintains the MarketAxess Holdings Inc. 2020 Equity Incentive Plan (the “2020 Plan”), which provides for the grant of stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance units, or other stock-based awards as incentives to encourage employees, consultants and non-employee directors to participate in the long-term success of the Company. As of June 30, 2023, there were 2,429,781 shares available for grant under the 2020 Plan.

Total stock-based compensation expense was as follows:


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
	(In thousands)
Employees	$	6,647	$	6,059	$	13,747	$	13,701
Non-employee directors		243		444		631		901
Total stock-based compensation	$	6,890	$	6,503	$	14,378	$	14,602

The Company records stock-based compensation expense for employees in employee compensation and benefits and for non-employee directors in general and administrative expenses in the Consolidated Statements of Operations.

During the six months ended June 30, 2023, the Company granted a total of (i) 72,777 restricted stock units, (ii) 13,908 options to purchase shares of common stock and (iii) performance stock units with an expected pay-out at target of 23,302 shares of common stock. The fair values of the restricted stock units and performance stock units were based on a weighted-average fair value per unit at the grant date of $353.63 and $386.14, respectively. Based on the Black-Scholes option pricing model, the weighted-average fair value for each option granted was $123.47 per share.

Included in the above totals are shares granted in April 2023 to the Company’s Chief Executive Officer in connection with his appointment to the position, consisting of: (i) 2,729 restricted stock units with a grant date fair value of $1.05 million, as determined by the Company’s Compensation and Talent Committee by dividing the award value by the average closing price of the Company’s common stock on the ten trading days leading up to and including the grant date, rounded to the nearest whole number; and (ii) 5,039 target performance stock units with a grant date fair value of $2.45 million, as determined by the Company’s Compensation and Talent Committee using the Monte Carlo method. The restricted stock units vest 25% on each of the third and fourth anniversary of the grant date and 50% on the fifth anniversary of the grant date, subject to continued service through the respective vesting dates. The performance stock units vest 25% on each of the third and fourth anniversaries of the grant date and 50% on the fifth anniversary of the grant date, subject to certification of the performance criteria and continued service through the respective vesting dates.

As of June 30, 2023, the total unrecognized compensation cost related to all non-vested awards was $55.0 million. That cost is expected to be recognized over a weighted-average period of 1.6 years.

The Company maintains the MarketAxess Holdings Inc. 2022 Employee Stock Purchase Plan (the “ESPP”). The ESPP has a series of six-month offering periods, with a new offering period beginning on the first trading day on or after February 16 and August 16 of each year. Subject to certain limitations, employees may contribute up to $2,000 of such employee’s total eligible compensation per month towards the purchase of common stock via payroll deductions. Shares are purchased at a 15% discount off the lesser of: (i) the fair market value per share on the first day of each offering period; and (ii) the fair market value per share on the purchase date, but in no event less than par value. The Company issued 1,928 shares of common stock on February 15, 2023 under the ESPP. As of June 30, 2023, there were 119,293 shares available for purchase under the ESPP.