Net Loss Per Share

Basic net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding during each period. Diluted net (loss) income per share is calculated by dividing net (loss) income by the diluted number of shares outstanding during each period. Except where the result would be anti-dilutive to net loss, diluted net loss per share would be calculated assuming the impact of the conversion of the 2023 Notes, the exercise of outstanding equity compensation awards, ordinary shares expected to be issued under our employee stock purchase plan (“ESPP”) and the exercise of contingent consideration warrants, all which have been exercised or have expired during the first quarter of 2018.

We have a choice to settle the conversion obligation under the 2023 Notes in cash, shares or any combination of the two. We utilize the if-converted method to reflect the impact of the conversion of the 2023 Notes, unless the result is anti-dilutive. This method assumes the conversion of the 2023 Notes into shares of our ordinary shares and reflects the elimination of the interest expense related to the 2023 Notes.

The dilutive effect of the warrants, stock options, RSU’s and ordinary shares expected to be issued under or ESPP has been calculated using the treasury stock method.

A reconciliation of basic and diluted net loss per share, together with the related shares outstanding in thousands is as follows:



	Three Months Ended June 30,						Six Months Ended June 30,
Net Loss Per Share:	2019			2018			2019			2018

Net loss	$	(8,605	)	$	(3,438	)	$	(21,623	)	$	(15,674	)

Weighted average shares:
Basic shares	37,356			36,772			37,355			37,666
Effect of dilutive securities—employee and director equity awards outstanding and 2023 Notes	—			—			—			—
Diluted shares	37,356			36,772			37,355			37,666

Net loss per share - basic	$	(0.23	)	$	(0.09	)	$	(0.58	)	$	(0.42	)
Net loss per share - diluted	$	(0.23	)	$	(0.09	)	$	(0.58	)	$	(0.42	)

Potential common shares of 20,359 and 18,831 were excluded from the calculation of weighted average shares for the three months ended June 30, 2019 and 2018, respectively, because their effect was considered to be anti-dilutive. Potential common shares of 20,502 and 15,300 were excluded from the calculation of weighted average shares for the six months ended June 30, 2019 and 2018, respectively. For the three and six months ended June 30, 2019 and 2018, the effects of dilutive securities were entirely excluded from the calculation of net loss per share as a net loss was reported in this period.