Prior to November 1, 2013, Ceridian employees participated in a share-based compensation plan of the former ultimate parent of Ceridian, the 2007 Stock Incentive Plan (“2007 SIP”). Effective November 1, 2013, although most participants who held stock options under the 2007 SIP converted their options to a newly created option plan, the 2013 Ceridian HCM Holding Inc. Stock Incentive Plan, as amended (“2013 SIP”), a small number of participants maintained their stock options in the 2007 SIP. Concurrent with the IPO and legal reorganization, all outstanding stock options under the 2007 SIP were converted into options to purchase common stock of Ceridian. As of March 31, 2020, there were 2,500 stock options outstanding under the 2007 SIP.

Stock options awarded under the 2013 SIP vest either annually on a pro rata basis over a four- or five-year period or on a specific date if certain performance criteria are satisfied and certain equity values are attained. In addition, upon termination of service, all vested options must be exercised generally within 90 days after termination, or these awards will be forfeited. The stock option awards have a 10-year contractual term and have an exercise price that is not less than the fair market value of the underlying stock on the date of grant. As of March 31, 2020, there were 4,657,548 stock options and restricted stock units outstanding under the 2013 SIP. We do not intend to grant any additional awards under the 2007 SIP or the 2013 SIP.

On April 24, 2018, in connection with the IPO, the Board of Directors approved the Ceridian HCM Holding Inc. 2018 Equity Incentive Plan (“2018 EIP”), which authorizes the issuance of up to 13,500,000 shares of common stock to eligible participants through equity awards. (the “Share Reserve”). The Share Reserve may be increased on March 31 of each of the first ten calendar years during the term of the 2018 EIP, by the lesser of (i) three percent of the number of shares of our common stock outstanding on each January 31 immediately prior to the date of increase or (ii) such number of shares of our common stock determined by the Board of Directors. On March 31, 2020, the Share Reserve was increased by three percent of the number of shares of common stock outstanding on January 31, 2020, or 4,335,286 shares.

Equity awards under the 2018 EIP vest annually on a pro rata basis, generally over a four-year period. In addition, upon termination of service, all vested awards must be exercised within 90 days after termination, or these awards will be forfeited. The equity awards have a 10-year contractual term and have an exercise price that is not less than the fair market value of the underlying stock on the date of the grant. As of March 31, 2020, there were 9,164,882 stock options, restricted stock units, and performance stock units outstanding and 12,866,597 shares available for future grants of equity awards under the 2018 EIP.

On November 9, 2018, the Board of Directors approved the Ceridian HCM Holding Inc. Global Employee Stock Purchase Plan (the “GESPP”), and the Company’s stockholders approved the GESPP on May 1, 2019. The GESPP authorizes the issuance of up to 2,500,000 shares of common stock to eligible participants through purchases via payroll deductions. The purchase price is the lower of (i) 85% of the fair market value of a share of common stock on the offering date (the first trading day of the offering period commencing on January 1 and concluding on December 31) or (ii) 85% of the fair market value of a share of common stock on the purchase date. The GESPP shall continue for ten years, unless terminated sooner as provided under the GESPP. During 2020 and subsequent years, quarterly purchase periods will commence on January 1, April 1, July 1, and October 1. Shares will be purchased on the last trading day of the respective purchase periods. The first GESPP purchase period of 2020 ended on March 31, 2020, resulting in the issuance of 49,802 shares of our common stock at a purchase price of $42.56.

Total share-based compensation expense was $12.5 million and $6.0 million for the three months ended March 31, 2020, and 2019, respectively.

Performance-based option activity under the 2007 SIP and the 2013 SIP for the period was as follows:

	Shares			Weighted Average Exercise Price (per share)			Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Performance-based options outstanding at December 31, 2019		68,281		$	13.58			2.6	$	3.7
Granted		—			—			—		—
Exercised		(13,417	)		(13.46	)		—		—
Forfeited or expired		—			—			—		—
Performance-based options outstanding at March 31, 2020		54,864		$	13.61			2.4	$	2.0
Performance-based options exercisable at March 31, 2020		54,864		$	13.61			2.4	$	2.0

The performance criteria for all outstanding performance-based stock options was met on June 7, 2018, resulting in the vesting of all outstanding performance-based stock options on this date. As of March 31, 2020, there was no share-based compensation expense related to unvested performance-based stock options not yet recognized.

Term-based option activity, including stock options under the 2007 SIP, the 2013 SIP, and the 2018 EIP, for the period was as follows:

	Shares			Weighted Average Exercise Price (per share)			Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Term-based options outstanding at December 31, 2019		13,144,937		$	29.74			7.8	$	501.3
Granted		140,447			70.73			—		—
Exercised		(476,489	)		(18.84	)		—		—
Forfeited or expired		(51,324	)		(29.34	)		—		—
Term-based options outstanding at March 31, 2020		12,757,571		$	30.60			7.6	$	251.6
Term-based options exercisable at March 31, 2020		4,668,339		$	25.02			6.5	$	116.9

As of March 31, 2020, there was $75.9 million of share-based compensation expense related to unvested term-based awards not yet recognized, which is expected to be recognized over a weighted average period of 1.9 years.

Restricted stock units (“RSUs”) activity, including RSUs under the 2013 SIP and the 2018 EIP, for the period was as follows:

	Shares
RSUs outstanding at December 31, 2019		819,818
Granted		60,325
Shares issued upon vesting of RSUs		(12,500	)
Forfeited or canceled		(54	)
RSUs outstanding at March 31, 2020		867,589
RSUs releasable at March 31, 2020		395,338

During the three months ended March 31, 2020, 138,687 RSUs vested. As of March 31, 2020, there were 472,251 unvested RSUs outstanding and 395,338 vested RSUs outstanding. RSUs generally vest annually over a one-, three-, or four-year period. As of March 31, 2020, there was $16.5 million of share-based compensation expense related to unvested RSUs not yet recognized, which is expected to be recognized over a weighted average period of 1.7 years.

During the three months ended March 31, 2020, 145,017 performance stock units (“PSUs”) were granted under the 2018 EIP and had a weighted average grant date fair value per share of $70.73. During the three months ended March 31, 2020, 111 PSUs were forfeited and cancelled.

The vesting conditions for the PSUs are based on the Company’s performance against Cloud revenue and adjusted EBITDA margin goals under the Company’s 2020 Management Incentive Plan (the “2020 MIP”) for the incentive period of January 1, 2020 through December 31, 2020. The maximum incentive vesting of PSUs may not exceed 125% under the 2020 MIP. Both the Cloud revenue and adjusted EBITDA margin goals are calculated based on the Company’s operating results, adjusted for foreign currency and interest rate impacts plus other unique impacts as approved by the Compensation Committee or the Board. Upon vesting of a PSU, a participant will receive shares of common stock of the Company. The probability of vesting of PSUs will continue to be evaluated throughout the period, and share-based compensation expense will be recognized in accordance with that probability. As of March 31, 2020, there was $10.3 million of share-based compensation expense related to unvested PSUs not yet recognized.