XOMA Corporation Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Tables)

Stock-based Compensation (Tables)

3 Months Ended

Mar. 31, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

The fair value of the stock options granted during the three months ended March 31, 2019 and 2018, was estimated based on the following weighted average assumptions:

	Three Months Ended March 31,
	2019			2018
Dividend yield		0	%		0	%
Expected volatility		103	%		101	%
Risk-free interest rate		2.55	%		2.72	%
Expected term	5.60 years			5.60 years

Stock Option Activity

Stock option activity for the three months ended March 31, 2019, was as follows:

	Number of shares			Weighted Average Exercise Price Per Share		Weighted Average Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding at beginning of year		1,624,746		$	23.09
Granted		349,979			14.23
Exercised		(23,861	)		4.83
Forfeited, expired or cancelled		(32,914	)		64.36
Outstanding at end of period		1,917,950		$	20.99		7.9	$	7,624
Exercisable at end of period		1,134,601		$	24.42		7.1	$	6,046

Stock-based Compensation Expense

The following table shows total stock-based compensation expense for stock options, RSUs and ESPP in the condensed consolidated statements of operations and comprehensive income (loss) (in thousands):

	Three Months Ended March 31,
	2019		2018
Research and development	$	49	$	104
General and administrative		1,679		1,312
Total stock-based compensation expense	$	1,728	$	1,416