Our Amended and Restated Long Term Incentive Plan (the “LTIP”) provides for the issuance of Glatfelter common stock to eligible participants in the form of restricted stock units, restricted stock awards, non-qualified stock options, performance shares, incentive stock options and performance units. As of December 31, 2020, there were 1,899,527 shares of common stock available for future issuance under the LTIP.

Pursuant to the terms of the LTIP, we have issued to eligible participants restricted stock units, performance share awards and stock only stock appreciation rights (“SOSARs”).

Restricted Stock Units (“RSUs”) and Performance Share Awards (“PSAs”)Awards of RSUs and PSAs are made under our LTIP. The vesting of RSUs is generally based on the passage of time, generally over a three -year period or in certain instances the RSUs were issued with five-year cliff vesting. PSAs are issued to members of management and vesting is based on achievement of cumulative financial performance targets covering a two-year period followed by an additional one-year service period. The performance measures include a minimum, target and maximum performance level providing the grantees an opportunity to receive more or less shares than targeted depending on actual financial performance. In addition, beginning in 2018, PSA awards include a modifier based on the three-year total shareholder return relative to a broad market index. For RSUs the grant date fair value of the awards, or the closing price per common share on the date of the award, is used to determine the amount of expense to be recognized over the applicable service period. For PSAs, the grant date fair value is estimated using a lattice model. The significant inputs include the stock price, volatility, dividend yield, and risk-free rate of return. Settlement of RSUs and PSAs will be made in shares of our common stock currently held in treasury.

The following table summarizes RSU and PSA activity during the past three years:

Units	2020			2019			2018
Balance at January 1,		896,463			756,786			929,386
Granted		400,854			600,820			435,542
Forfeited		(89,483	)		(223,677	)		(112,501	)
Shares delivered		(136,182	)		(237,466	)		(495,641	)
Balance at December 31,		1,071,652			896,463			756,786

The amount granted in 2020, 2019 and 2018 includes 171,150, 218,422 and 184,834 PSAs, respectively, exclusive of reinvested dividends. The weighted average grant date fair value per unit for awards in 2020, 2019 and 2018 was $16.65, $15.86 and $20.20, respectively. As of December 31, 2020, unrecognized compensation expense for outstanding RSUs and PSAs totaled $5.4 million. The weighted average remaining period over which the expense will be recognized is 1.6 years.

	2020					2019					2018
SOSARS	Shares			Wtd Avg Exercise Price		Shares			Wtd Avg Exercise Price		Shares			Wtd Avg Exercise Price
Outstanding at January 1,		1,291,947		$	20.05		2,334,742		$	18.08		2,561,846		$	17.87
Granted		—			—		—			—		—			—
Exercised		(58,460	)		12.85		(596,360	)		15.56		(158,545	)		13.31
Canceled / forfeited		(151,074	)		20.25		(446,435	)		21.06		(68,559	)		21.09
Outstanding at December 31,		1,082,413		$	20.40		1,291,947		$	20.05		2,334,742		$	18.08
Exercisable at December 31,		1,082,413			20.40		1,291,947		20.05			2,134,297			18.13
Vested and expected to vest		1,082,413					1,291,947					2,334,742
Compensation expense (in thousands)	$	—				$	40				$	317

Under terms of the SOSAR, the recipients receive the right to receive a payment in the form of shares of common stock equal to the difference, if any, in the fair market value of one share of common stock at the time of exercising the SOSAR and the exercise price. The SOSARs vest ratably over a three-year period. No SOSARs were issued during any of the past three years. As of December 31, 2020, the intrinsic value of SOSARs vested and expected to vest totaled $0.1 million and the remaining weighted average contractual life of outstanding SOSARs was 3.5 years.