5. Earnings per Common Share

Basic earnings (loss) per common share is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. For diluted earnings per common share, the denominator also includes the dilutive effect of outstanding restricted stock units determined using the treasury stock method. Dilutive effects of contingently issuable shares are included in the weighted average dilutive share calculation when the contingencies have been resolved. For periods in which net losses are generated, the dilutive potential common shares are excluded from the calculation of diluted earnings per share as the effect would be anti-dilutive.

The following table sets forth the computation of basic and diluted earnings per common share (in thousands, except per share amounts):

	Three Months Ended					Nine Months Ended
	October 2,		September 26,			October 2,			September 26,
	2015		2014			2015			2014
Numerators:
Income from continuing operations	$	6,568	$	5,119		$	29,525		$	11,381
Loss from discontinued operations		—		(594	)		(13	)		(5,138	)
Less: Income attributable to noncontrolling interest		—		—			—			(10	)
Loss from discontinued operations attributable to GSI Group Inc.		—		(594	)		(13	)		(5,148	)
Net income attributable to GSI Group Inc.	$	6,568	$	4,525		$	29,512		$	6,233

Denominators:
Weighted average common shares outstanding— basic		34,599		34,389			34,578			34,333
Dilutive potential common shares		456		404			449			392
Weighted average common shares outstanding— diluted		35,055		34,793			35,027			34,725
Antidilutive common shares excluded from above		—		—			—			29

Basic Earnings (Loss) per Common Share:
From continuing operations	$	0.19	$	0.15		$	0.85		$	0.33
From discontinued operations	$	—	$	(0.02	)	$	(0.00	)	$	(0.15	)
Basic earnings per share attributable to GSI Group Inc.	$	0.19	$	0.13		$	0.85		$	0.18

Diluted Earnings (Loss) per Common Share:
From continuing operations	$	0.19	$	0.15		$	0.84		$	0.33
From discontinued operations	$	—	$	(0.02	)	$	(0.00	)	$	(0.15	)
Diluted earnings per share attributable to GSI Group Inc.	$	0.19	$	0.13		$	0.84		$	0.18

Common Stock Repurchases

In October 2013, the Company’s Board of Directors authorized a share repurchase plan under which the Company may repurchase outstanding shares of the Company’s common stock up to an aggregate amount of $10.0 million. The shares may be repurchased from time to time, at the Company’s discretion, based on ongoing assessment of the capital needs of the business, the market price of the Company’s common stock, and general market conditions. Shares may also be repurchased through an accelerated stock purchase agreement, on the open market or in privately negotiated transactions in accordance with applicable federal securities laws. Repurchases may be made under certain SEC regulations, which would permit common stock to be purchased when the Company would otherwise be prohibited from doing so under insider trading laws. The share repurchase plan does not obligate the Company to acquire any particular amount of common stock. No time limit was set for the completion of the share repurchase program, and the program may be suspended or discontinued at any time. As of December 31, 2014, the Company had cumulatively repurchased 50 thousand shares of its common stock for an aggregate amount of $0.5 million. During the third quarter of 2015, the Company repurchased 77 thousand shares in the open market for an aggregate purchase price of $1.0 million at an average price of $13.03 per share.