non-employee

Under the 2013 Plan, the Company has issued RSAs to directors and restricted stock units (“RSUs”) to employees and independent contractors. RSAs vest in equal annual installments over a or three-year period from the date of grant. RSUs generally vest in equal annual installments over a five-year period from the date of grant or earlier as approved by the compensation committee of the Company’s board of directors. Any unvested awards are canceled upon termination as a service provider. As of March 31, 2020, there were no issued or outstanding options, SARs, performance units or performance share awards under the 2013 Plan.

During the three months ended March 31, 2020, 170,106 shares of RSUs were vested and 50,872 shares of common stock were withheld to pay applicable required employee statutory withholding taxes based on the market value of the shares on the vesting date. The shares withheld for taxes were returned to the share reserve and are available for future issuance in accordance with provisions of the 2013 Plan. During the three months ended March 31, 2020, there were no deferred stock units (“DSUs”) that settled.

Activity under the 2013 Plan consisted of the following (dollars in thousands, except weighted average per share data):

non-overlapping

6-month

6-month

The ESPP initially had 366,667 shares of common stock reserved, and 204,473 shares of common stock remain available for issuance for each of the periods ended as of March 31, 2020 and December 31, 2019, respectively. The ESPP provides for annual increases in the number of shares available for issuance under the ESPP, equal to the least of (i) 366,667 shares, (ii) 1% of the outstanding shares on such date, or (iii) an amount determined by the compensation committee of the board of directors. Pursuant to the provisions of the ESPP, the board of directors has determined to not provide for any annual increases to date. At March 31, 2020, total unrecognized compensation cost related to the ESPP was $23,000 and is expected to be recognized over a weighted average period of 0.12 years.

Prior to the IPO, certain employees were granted SARs. As of March 31, 2013, the outstanding SARs were frozen at the liability amount, and will be paid out to each participant in installments upon retirement or departure under the terms of the revised SARs agreements. To replace beneficial ownership in the SARs, the difference between the book value liability and the fair value of the awards was granted to plan participants in the form of DSUs, which were fully vested upon receipt and will be settled in actual stock at a rate of 20% per year if the participant remains employed by the Company during that period (otherwise all unsettled shares of stock upon termination from service will be settled five years from the termination date, unless otherwise agreed to by the Company). In the event of death or termination of service after reaching the age of 67, 100% of the DSUs will be settled. As of March 31, 2020, the remaining future share settlements of fully vested DSUs by year consisted of the following:

Components of stock-based compensation are included in selling, general and administrative expense in the condensed consolidated statements of net and comprehensive income and consisted of the following (in thousands):