Share-Based Payments

3 Months Ended

Mar. 31, 2020

Share-based Payment Arrangement [Abstract]

The table below presents share-based compensation expense included in each of the financial statement line items:



	Three Months Ended March 31,
	2020		2019
	(in thousands)
Research and development	$	1,935	$	1,087
General and administrative	2,888		2,387
Total share-based compensation expense	$	4,823	$	3,474

During the three months ended March 31, 2020, the Company granted 1,450,231 stock options with a per share weighted-average grant date fair value of $15.95 and 661,130 restricted stock units to its employees.

2018 and 2019 Performance-Based Restricted Stock Units

Since October 2018 through the end of 2019, the Company granted performance-based restricted stock units, or PSUs, to its employees. The vesting of PSUs is subject to the Company achieving up to three possible performance milestones related to the Company's active novel programs and the employees' continued employment with the Company. One sixth of the units will vest upon achievement of each milestone or, if achievement of the performance milestone occurs prior to the first anniversary of the grant date, on the first anniversary of the grant date. Additional one sixth of the units will vest on the one-year anniversary of the performance milestone achievement date. During the three months ended March 31, 2020, one of the performance milestones was met and 259,357 PSUs vested. For the three months ended March 31, 2020, the Company recognized approximately $0.7 million of stock-based compensation costs related to these awards. The remaining two performance milestones were not deemed probable as of March 31, 2020. As of March 31, 2020, up to 1,449,334 shares of the Company's common stock may be issued under unvested PSUs.

MOMENTA PHARMACEUTICALS INC 10-Q